Reversing Strings in C Programming

Reversing a string is a common operation in programming, and C is no exception. In this tutorial, we'll explore how to reverse a string in C programming using different methods.

Method 1: Using a Temporary Array

One way to reverse a string in C is to use a temporary array to store the characters of the original string in reverse order.

#include <stdio.h>
#include <string.h>

void reverse_string(char *str) {
    int length = strlen(str);
    char temp[length + 1];
    int i;

    for (i = 0; i < length; i++) {
        temp[i] = str[length - i - 1];
    }
    temp[length] = '\0';

    strcpy(str, temp);
}

int main() {
    char str[] = "Hello, World!";
    printf("Original string: %s\n", str);
    reverse_string(str);
    printf("Reversed string: %s\n", str);
    return 0;
}

Method 2: Using Two Pointers

Another way to reverse a string in C is to use two pointers, one starting from the beginning of the string and one from the end.

#include <stdio.h>
#include <string.h>

void reverse_string(char *str) {
    int length = strlen(str);
    char *start = str;
    char *end = str + length - 1;
    char temp;

    while (start < end) {
        temp = *start;
        *start = *end;
        *end = temp;
        start++;
        end--;
    }
}

int main() {
    char str[] = "Hello, World!";
    printf("Original string: %s\n", str);
    reverse_string(str);
    printf("Reversed string: %s\n", str);
    return 0;
}

Method 3: Using Recursion

We can also reverse a string in C using recursion.

#include <stdio.h>
#include <string.h>

void reverse_string(char *str) {
    if (*str == '\0') return;
    reverse_string(str + 1);
    printf("%c", *str);
}

int main() {
    char str[] = "Hello, World!";
    printf("Original string: %s\n", str);
    printf("Reversed string: ");
    reverse_string(str);
    printf("\n");
    return 0;
}

Conclusion

Reversing a string in C programming is a simple operation that can be achieved using different methods. In this tutorial, we've explored three methods: using a temporary array, using two pointers, and using recursion. Each method has its own advantages and disadvantages, and the choice of method depends on the specific requirements of the problem.