C program to concatenate two strings

PROGRAM:

#include <stdio.h>
int main()
{
    char s1[100], s2[100], i, j;

    printf("Enter first string: ");
    scanf("%s", s1);

    printf("Enter second string: ");
    scanf("%s", s2);

    
    for(i = 0; s1[i] != '\0'; ++i);

    for(j = 0; s2[j] != '\0'; ++j, ++i)
    {
        s1[i] = s2[j];
    }

    s1[i] = '\0';
    printf("After concatenation: %s", s1);

    return 0;
}

OUTPUT:

Enter first string: lol
Enter second string: :)
After concatenation: lol:)

Find the frequency of characters in a string Count the number of vowels, consonants and so on Remove all characters in a string except alphabet Find the length of a string Concatenate two strings Copy string without using strcpy() Sort elements in lexicographical order