Acest subiect va discuta mai multe moduri de a inversa un șir în limbajul de programare C. Inversarea unui șir este tehnica care inversează sau schimbă ordinea unui șir dat astfel încât ultimul caracter al șirului să devină primul caracter al șirului și așa mai departe. În plus, putem verifica și Palindromul șirului dat, inversând șirul original.
De exemplu, introducem un șir ' MĂR ', și apoi utilizați algoritmul invers. Algoritmul invers returnează șirul ' ELPPA ' care este complet invers față de șirul original.
Diferite moduri de a găsi reversul unui șir în C
Următoarele sunt diferitele modalități de a găsi reversul unui șir în limbajul de programare C:
- Inversați un șir folosind funcția strrev().
- Inversați un șir fără a utiliza funcția de bibliotecă
- Inversați un șir folosind funcția de recursie
- Inversați un șir folosind bucla for
- Inversați un șir folosind bucla while
- Inversați un șir folosind indicatori
- Inversați un șir pentru a verifica dacă există Palindrom
Programul 1: imprimați reversul unui șir folosind funcția strrev().
Să luăm în considerare un exemplu pentru a tipări reversul unui șir folosind funcția strrev().
Program1.c
java instanțiat
#include #include int main() { char str[40]; // declare the size of character string printf ('
Enter a string to be reversed: '); scanf ('%s', str); // use strrev() function to reverse a string printf ('
After the reverse of a string: %s ', strrev(str)); return 0; } Ieșire
Enter a string to be reversed: AMBULANCE After the reverse of a string: ECNALUBMA
Programul 2: Imprimați reversul unui șir fără a utiliza funcția de bibliotecă
Să luăm în considerare un exemplu pentru a imprima reversul unui șir folosind funcția definită de utilizator.
Programul2.c
#include #include // function definition of the revstr() void revstr(char *str1) { // declare variable int i, len, temp; len = strlen(str1); // use strlen() to get the length of str string // use for loop to iterate the string for (i = 0; i <len 2; i++) { temp variable use to temporary hold the string str1[i]="str1[len" - i 1]; str1[len 1]="temp;" } int main() char str[50]; size of printf (' enter string: '); gets(str); gets() function take
before reversing %s
', str); call revstr() revstr(str); after %s', < pre> <p> <strong>Output</strong> </p> <pre> Enter the string: Welcome Friends Before reversing the string: Welcome Friends After reversing the string: sdneirF emocleW </pre> <h3>Program 3: Print the reverse of a string using the recursion function</h3> <p>Let's consider an example to print the reverse of a string using the recursion function.</p> <p> <strong>Recursion function:</strong> A recursion function is a function that continuously calls the same function without using a looping statement.</p> <p> <strong>Program3.c</strong> </p> <pre> #include #include // use recursion function void revstr(char *str1) { // declare static variable static int i, len, temp; len = strlen(str1); // use strlen() to get the length of str string if (i <len 2){ temp variable use to temporary hold the string str1[i]="str1[len" - i 1]; str1[len 1]="temp;" i++; revstr(str1); recusively calls revstr() function } int main() { char str1[50]; size of printf (' enter string: '); gets(str1); gets() take
before reversing %s
', str1); call after %s', < pre> <p> <strong>Output</strong> </p> <pre> Enter the string: LIFE INSURANCE Before reversing the string: LIFE INSURANCE After reversing the string: ECNARUSNI EFIL </pre> <h3>Program 4: Print the reverse of a string using for loop</h3> <p>Let's consider an example to print the reverse of a string using for loop in C programming language.</p> <p> <strong>Program4.c</strong> </p> <pre> #include #include #include void main() { char str[50], temp; // define the size of str[] array int i, left, right, len; printf ('
Display a reverse string in the C:
'); printf (' ----------------------- '); printf ('
Enter a string to reverse order: '); scanf( '%s', &str); len = strlen(str); // get the length of the string left = 0; // set left index at 0 right = len - 1; // set right index len - 1 // use for loop to store the reverse string for (i = left; i <right; i++) { temp="str[i];" str[i]="str[right];" str[right]="temp;" right--; } printf (' the reverse of original string is: %s ', str); getch(); < pre> <p> <strong>Output</strong> </p> <pre> Display a reverse string in the C: ----------------------- Enter a string to reverse order: APPLE The reverse of the original string is: ELPPA </pre> <h3>Program 5: Print the reverse of a string using while loop</h3> <p>Let's consider an example to print the reverse of a string using while loop in C programming language.</p> <p> <strong>Program5.c</strong> </p> <pre> #include #include int main() { char str1[50], temp; // declare and initialize the size of string array. int i = 0, j =0; printf (' Enter a string to be reversed: '); scanf( '%s', str1); j = strlen (str1) - 1; // get the length of the string // use while loop to define the condition while ( i <j) 1 { use temp variable to store the characters of str1 str1[j]="str1[i];" str1[i]="temp;" i++; i incremented by j--; j is decremented } printf (' reversed string: %s', str1); return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reversed of the string: TNIOPTAVAJ </pre> <h3>Program 6: Print the reverse of a string using pointers</h3> <p>Let's consider an example to print the reverse of a string using pointers in the C programming language.</p> <p> <strong>Program6.c</strong> </p> <pre> #include #include int str_len( char *st); void revstr( char *st); int main() { char st[50]; printf (' Enter a string to be reversed: '); scanf( '%s', st); revstr(st); printf (' The reverse string is: %s', st); return 0; } void revstr (char *st) { int len, i; char *start, *end, temp; len = str_len (st); start = st; end = st; for (i = 0; i <len - 1; i++) end++; for (i="0;" i < len 2; { temp="*end;" *end="*start;" *start="temp;" start++; end--; } int str_len (char *ptr) while ( *(ptr + i) !=" " ) i++; return i; pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reverse string is: TNIOPTAVAJ </pre> <h3>Program 7: Program to check whether the reverse string is a Palindrome</h3> <p>Consider a program to check whether the given string is a palindrome or not in the C programming language.</p> <p> <strong>Program7.c</strong> </p> <pre> #include #include int main () { // declare variables char str1[30]; int i, len, flag = 0; printf (' Enter a string: '); scanf ('%s', str1); len = strlen( str1 ); // get the string length for ( i = 0; i <len; i++) { str1[i] is not equal to str1[len-i-1] if (str1[i] !="str1[len" - i 1]) flag="1;" break; exit from statement } (flag) printf (' %s a palindrome string', str1); else palindrome', return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: madam madam is a palindrome string. </pre> <hr></len;></pre></len></pre></j)></pre></right;></pre></len></pre></len> Programul 3: Imprimați reversul unui șir folosind funcția de recursivitate
Să luăm în considerare un exemplu pentru a imprima reversul unui șir folosind funcția de recursivitate.
Funcția de recursivitate: O funcție de recursivitate este o funcție care apelează continuu aceeași funcție fără a utiliza o instrucțiune de buclă.
java adauga la o matrice
Program3.c
#include #include // use recursion function void revstr(char *str1) { // declare static variable static int i, len, temp; len = strlen(str1); // use strlen() to get the length of str string if (i <len 2){ temp variable use to temporary hold the string str1[i]="str1[len" - i 1]; str1[len 1]="temp;" i++; revstr(str1); recusively calls revstr() function } int main() { char str1[50]; size of printf (\' enter string: \'); gets(str1); gets() take
before reversing %s
\', str1); call after %s\', < pre> <p> <strong>Output</strong> </p> <pre> Enter the string: LIFE INSURANCE Before reversing the string: LIFE INSURANCE After reversing the string: ECNARUSNI EFIL </pre> <h3>Program 4: Print the reverse of a string using for loop</h3> <p>Let's consider an example to print the reverse of a string using for loop in C programming language.</p> <p> <strong>Program4.c</strong> </p> <pre> #include #include #include void main() { char str[50], temp; // define the size of str[] array int i, left, right, len; printf ('
Display a reverse string in the C:
'); printf (' ----------------------- '); printf ('
Enter a string to reverse order: '); scanf( '%s', &str); len = strlen(str); // get the length of the string left = 0; // set left index at 0 right = len - 1; // set right index len - 1 // use for loop to store the reverse string for (i = left; i <right; i++) { temp="str[i];" str[i]="str[right];" str[right]="temp;" right--; } printf (\' the reverse of original string is: %s \', str); getch(); < pre> <p> <strong>Output</strong> </p> <pre> Display a reverse string in the C: ----------------------- Enter a string to reverse order: APPLE The reverse of the original string is: ELPPA </pre> <h3>Program 5: Print the reverse of a string using while loop</h3> <p>Let's consider an example to print the reverse of a string using while loop in C programming language.</p> <p> <strong>Program5.c</strong> </p> <pre> #include #include int main() { char str1[50], temp; // declare and initialize the size of string array. int i = 0, j =0; printf (' Enter a string to be reversed: '); scanf( '%s', str1); j = strlen (str1) - 1; // get the length of the string // use while loop to define the condition while ( i <j) 1 { use temp variable to store the characters of str1 str1[j]="str1[i];" str1[i]="temp;" i++; i incremented by j--; j is decremented } printf (\' reversed string: %s\', str1); return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reversed of the string: TNIOPTAVAJ </pre> <h3>Program 6: Print the reverse of a string using pointers</h3> <p>Let's consider an example to print the reverse of a string using pointers in the C programming language.</p> <p> <strong>Program6.c</strong> </p> <pre> #include #include int str_len( char *st); void revstr( char *st); int main() { char st[50]; printf (' Enter a string to be reversed: '); scanf( '%s', st); revstr(st); printf (' The reverse string is: %s', st); return 0; } void revstr (char *st) { int len, i; char *start, *end, temp; len = str_len (st); start = st; end = st; for (i = 0; i <len - 1; i++) end++; for (i="0;" i < len 2; { temp="*end;" *end="*start;" *start="temp;" start++; end--; } int str_len (char *ptr) while ( *(ptr + i) !=" " ) i++; return i; pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reverse string is: TNIOPTAVAJ </pre> <h3>Program 7: Program to check whether the reverse string is a Palindrome</h3> <p>Consider a program to check whether the given string is a palindrome or not in the C programming language.</p> <p> <strong>Program7.c</strong> </p> <pre> #include #include int main () { // declare variables char str1[30]; int i, len, flag = 0; printf (' Enter a string: '); scanf ('%s', str1); len = strlen( str1 ); // get the string length for ( i = 0; i <len; i++) { str1[i] is not equal to str1[len-i-1] if (str1[i] !="str1[len" - i 1]) flag="1;" break; exit from statement } (flag) printf (\' %s a palindrome string\', str1); else palindrome\', return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: madam madam is a palindrome string. </pre> <hr></len;></pre></len></pre></j)></pre></right;></pre></len> Programul 4: Imprimați reversul unui șir folosind bucla for
Să luăm în considerare un exemplu pentru a tipări reversul unui șir folosind bucla for în limbajul de programare C.
Program4.c
#include #include #include void main() { char str[50], temp; // define the size of str[] array int i, left, right, len; printf ('
Display a reverse string in the C:
'); printf (' ----------------------- '); printf ('
Enter a string to reverse order: '); scanf( '%s', &str); len = strlen(str); // get the length of the string left = 0; // set left index at 0 right = len - 1; // set right index len - 1 // use for loop to store the reverse string for (i = left; i <right; i++) { temp="str[i];" str[i]="str[right];" str[right]="temp;" right--; } printf (\' the reverse of original string is: %s \', str); getch(); < pre> <p> <strong>Output</strong> </p> <pre> Display a reverse string in the C: ----------------------- Enter a string to reverse order: APPLE The reverse of the original string is: ELPPA </pre> <h3>Program 5: Print the reverse of a string using while loop</h3> <p>Let's consider an example to print the reverse of a string using while loop in C programming language.</p> <p> <strong>Program5.c</strong> </p> <pre> #include #include int main() { char str1[50], temp; // declare and initialize the size of string array. int i = 0, j =0; printf (' Enter a string to be reversed: '); scanf( '%s', str1); j = strlen (str1) - 1; // get the length of the string // use while loop to define the condition while ( i <j) 1 { use temp variable to store the characters of str1 str1[j]="str1[i];" str1[i]="temp;" i++; i incremented by j--; j is decremented } printf (\' reversed string: %s\', str1); return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reversed of the string: TNIOPTAVAJ </pre> <h3>Program 6: Print the reverse of a string using pointers</h3> <p>Let's consider an example to print the reverse of a string using pointers in the C programming language.</p> <p> <strong>Program6.c</strong> </p> <pre> #include #include int str_len( char *st); void revstr( char *st); int main() { char st[50]; printf (' Enter a string to be reversed: '); scanf( '%s', st); revstr(st); printf (' The reverse string is: %s', st); return 0; } void revstr (char *st) { int len, i; char *start, *end, temp; len = str_len (st); start = st; end = st; for (i = 0; i <len - 1; i++) end++; for (i="0;" i < len 2; { temp="*end;" *end="*start;" *start="temp;" start++; end--; } int str_len (char *ptr) while ( *(ptr + i) !=" " ) i++; return i; pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reverse string is: TNIOPTAVAJ </pre> <h3>Program 7: Program to check whether the reverse string is a Palindrome</h3> <p>Consider a program to check whether the given string is a palindrome or not in the C programming language.</p> <p> <strong>Program7.c</strong> </p> <pre> #include #include int main () { // declare variables char str1[30]; int i, len, flag = 0; printf (' Enter a string: '); scanf ('%s', str1); len = strlen( str1 ); // get the string length for ( i = 0; i <len; i++) { str1[i] is not equal to str1[len-i-1] if (str1[i] !="str1[len" - i 1]) flag="1;" break; exit from statement } (flag) printf (\' %s a palindrome string\', str1); else palindrome\', return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: madam madam is a palindrome string. </pre> <hr></len;></pre></len></pre></j)></pre></right;> Programul 5: Imprimați reversul unui șir folosind bucla while
Să luăm în considerare un exemplu pentru a imprima reversul unui șir folosind bucla while în limbajul de programare C.
Program5.c
#include #include int main() { char str1[50], temp; // declare and initialize the size of string array. int i = 0, j =0; printf (' Enter a string to be reversed: '); scanf( '%s', str1); j = strlen (str1) - 1; // get the length of the string // use while loop to define the condition while ( i <j) 1 { use temp variable to store the characters of str1 str1[j]="str1[i];" str1[i]="temp;" i++; i incremented by j--; j is decremented } printf (\' reversed string: %s\', str1); return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reversed of the string: TNIOPTAVAJ </pre> <h3>Program 6: Print the reverse of a string using pointers</h3> <p>Let's consider an example to print the reverse of a string using pointers in the C programming language.</p> <p> <strong>Program6.c</strong> </p> <pre> #include #include int str_len( char *st); void revstr( char *st); int main() { char st[50]; printf (' Enter a string to be reversed: '); scanf( '%s', st); revstr(st); printf (' The reverse string is: %s', st); return 0; } void revstr (char *st) { int len, i; char *start, *end, temp; len = str_len (st); start = st; end = st; for (i = 0; i <len - 1; i++) end++; for (i="0;" i < len 2; { temp="*end;" *end="*start;" *start="temp;" start++; end--; } int str_len (char *ptr) while ( *(ptr + i) !=" " ) i++; return i; pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reverse string is: TNIOPTAVAJ </pre> <h3>Program 7: Program to check whether the reverse string is a Palindrome</h3> <p>Consider a program to check whether the given string is a palindrome or not in the C programming language.</p> <p> <strong>Program7.c</strong> </p> <pre> #include #include int main () { // declare variables char str1[30]; int i, len, flag = 0; printf (' Enter a string: '); scanf ('%s', str1); len = strlen( str1 ); // get the string length for ( i = 0; i <len; i++) { str1[i] is not equal to str1[len-i-1] if (str1[i] !="str1[len" - i 1]) flag="1;" break; exit from statement } (flag) printf (\' %s a palindrome string\', str1); else palindrome\', return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: madam madam is a palindrome string. </pre> <hr></len;></pre></len></pre></j)> Programul 6: Imprimați reversul unui șir folosind pointeri
Să luăm în considerare un exemplu pentru a imprima reversul unui șir folosind pointeri în limbajul de programare C.
Program6.c
#include #include int str_len( char *st); void revstr( char *st); int main() { char st[50]; printf (' Enter a string to be reversed: '); scanf( '%s', st); revstr(st); printf (' The reverse string is: %s', st); return 0; } void revstr (char *st) { int len, i; char *start, *end, temp; len = str_len (st); start = st; end = st; for (i = 0; i <len - 1; i++) end++; for (i="0;" i < len 2; { temp="*end;" *end="*start;" *start="temp;" start++; end--; } int str_len (char *ptr) while ( *(ptr + i) !=" " ) i++; return i; pre> <p> <strong>Output</strong> </p> <pre> Enter a string to be reversed: JAVATPOINT The reverse string is: TNIOPTAVAJ </pre> <h3>Program 7: Program to check whether the reverse string is a Palindrome</h3> <p>Consider a program to check whether the given string is a palindrome or not in the C programming language.</p> <p> <strong>Program7.c</strong> </p> <pre> #include #include int main () { // declare variables char str1[30]; int i, len, flag = 0; printf (' Enter a string: '); scanf ('%s', str1); len = strlen( str1 ); // get the string length for ( i = 0; i <len; i++) { str1[i] is not equal to str1[len-i-1] if (str1[i] !="str1[len" - i 1]) flag="1;" break; exit from statement } (flag) printf (\' %s a palindrome string\', str1); else palindrome\', return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: madam madam is a palindrome string. </pre> <hr></len;></pre></len> Programul 7: Program pentru a verifica dacă șirul invers este un Palindrom
Luați în considerare un program pentru a verifica dacă șirul dat este un palindrom sau nu în limbajul de programare C.
ce este desktop.ini
Program7.c
#include #include int main () { // declare variables char str1[30]; int i, len, flag = 0; printf (' Enter a string: '); scanf ('%s', str1); len = strlen( str1 ); // get the string length for ( i = 0; i <len; i++) { str1[i] is not equal to str1[len-i-1] if (str1[i] !="str1[len" - i 1]) flag="1;" break; exit from statement } (flag) printf (\\' %s a palindrome string\\', str1); else palindrome\\', return 0; < pre> <p> <strong>Output</strong> </p> <pre> Enter a string: madam madam is a palindrome string. </pre> <hr></len;>