program to concatenate two strings in c

Code Example 1

// this program is to contenate strings without using string function  #include <stdio.h> #include <string.h>  void concatenate(char *str1, char *str2) {     int i = strlen(str1), j = 0;      while (str2[j] != '\0')     {         str1[i] = str2[j];         i++;         j++;     }      str1[i] = '\0';  // declaring the end of the string }  int main() {   char string1[20], string2[20];   gets(string1);   gets(string2);      concatenate(string1, string2);      printf("String 1 : ");   puts(string1);      return 0; }

Code Example 2

#include <stdio.h> #include <string.h> int main() {   char a[1000], b[1000];    printf("Enter the first string\n");   gets(a);    printf("Enter the second string\n");   gets(b);    strcat(a, b);    printf("String obtained on concatenation: %s\n", a);    return 0; }