STRCAT implementation in C

Method 1:

//Program to implement strcat

#include <stdio.h>

void my_strcat( char *dest, const char *src){
(*dest)? my_strcat(++dest, src):(*dest++ = *src++)?my_strcat(dest, src):0;
}

int main(){
    char dest[30] = "Umesh ";
    char *src = "Joga";
    my_strcat(dest, src);
    printf("Dest = %s\n", dest);
    getchar();
    return 0;
}

#if 0
Explanation:
1. my_strcat(dest, src) copies data of src to dest. 
2. To do so, it first reaches end of the string dest using recursive 
calls my_strcat(++dest, src). 
3. Once end of dest is reached, data is copied using (*dest++ = *src++)? 
 my_strcat(dest, src).
#endif


Method 2

#include <stdio.h>

char *my_strcat(char *dest, const char *src){
    int i, j;
    for(i = 0; dest[i] != '\0'; i++);
    //printf("Val of i = %d\n", i);
    for(j = 0; src[j] != '\0'; j++)
        dest[i+j] = src[j];
    //printf("Val of j = %d\n", j);
    dest[i+j] = '\0';
    return dest;
}

Method 3 
//Using pointer

char *mystrcat(char *dest, const char *src){
    while(*dest) dest++;
    while(*dest++ = *src++);
    return dest;
}

int main(){
    char *src = "Joga";
    char dest[20] = "Umesh ";
    printf("Dest = %s\n", my_strcat(dest, src));
    getchar();
    return 0;
}