CODE EXAMPLE FOR C

not repeated serial number in c

#include <stdio.h>   
 int main()   
 {   
     int a, b, c;   
     for (a = 1; a <= 3; a++) {   
         for (b = 1; b <= 3 && b != a; b++) {   
             for (c = 1; c <= 3 && c != a && c != b; c++) {   
                 printf ("%d, %d, %d
", a, b, c);   
             }   
         }   
     }   
     return 0;   
 }