View difference between Paste ID: eJuu0y10 and UpEZckeS

 /*   Writing own version of the "   strcat( )   "  library function which is named mystrcat( )   */
 #include<stdio.h>
 void mystrcat(char s1[],char s2[]);
 int main(void)
 {
     char a[999999];
     char b[999999];
     gets(a);
     gets(b);
     mystrcat(a,b);
     return 0;
 }
 void mystrcat(char s1[],char s2[])
 {
     char s3[80];
     int i,j;
     for(i=0;s1[i]!='\0';i++)
     {
         s3[i]=s1[i];
     }
     for(j=0;s2[j]!='\0';j++)
     {
         s3[i]=s2[j];
         i++;
     }
     s3[i]='\0';
     puts(s3);
 }