Not using a look-up table

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
// Function prototypes:
int main();
int multi(int, int);
// Global variables:
int i=0;
int c=0;
int main()
{
    // Clears console (might not work with Visual Studio 2010, but okay with Code::Blocks)
    system("cls");
    //printf("Multiplying not using a look-up table:\n");
    // Loop:
    for(i=0; i<13; i=i+1)
    {
        // Nested loop:
        for(c=0; c<13; c=c+1)
        {
            printf("%d x %d = %d\n",i,c,multi(i,c));
        }
    }
    return 0;
}
// Returns multiplied values:
int multi(int x, int y)
{
    return x*y;
}
// Donkeysoft MMXII