#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
int main() {
    char *str1, *str2, *result;
    int len1, len2;
 
    // Step 1: Input first string dynamically
    str1 = (char *)malloc(100 * sizeof(char));
    if (str1 == NULL) {
        printf("Memory allocation failed for str1!\n");
        return 1;
    }
    printf("Enter first string: ");
    fgets(str1, 100, stdin);
    str1[strcspn(str1, "\n")] = '\0';  // Remove newline character
 
    // Step 2: Input second string dynamically
    str2 = (char *)malloc(100 * sizeof(char));
    if (str2 == NULL) {
        printf("Memory allocation failed for str2!\n");
        free(str1);
        return 1;
    }
    printf("Enter second string: ");
    fgets(str2, 100, stdin);
    str2[strcspn(str2, "\n")] = '\0';  // Remove newline
 
    // Step 3: Calculate lengths
    len1 = strlen(str1);
    len2 = strlen(str2);
 
    // Step 4: Allocate memory for concatenated string
    result = (char *)malloc((len1 + len2 + 1) * sizeof(char));
    if (result == NULL) {
        printf("Memory allocation failed for result!\n");
        free(str1);
        free(str2);
        return 1;
    }
 
    // Step 5: Concatenate strings manually
    strcpy(result, str1);
    strcat(result, str2);
 
    // Step 6: Display result
    printf("\nConcatenated String: %s\n", result);
 
    // Step 7: Free allocated memory
    free(str1);
    free(str2);
    free(result);
 
    return 0;
}