Print triangles with 4 arguments

#include <stdio.h>
#define SIZE 10


void pr_it(int,int,char,char);//

int main()
{
    int i,j;
    pr_it(SIZE,0,'*',' ');//second arg is variant of forumla for border-value
    pr_it(SIZE,1,'*',' ');//unknown at time of passing,so can;t be passed as value
    pr_it(SIZE,2,' ','*');
    pr_it(SIZE,3,' ','*');

    return 0;
}
void pr_it(int s,int flag,char c1,char c2)
{
    int i,j,border;//border -place where ' ' changes to '*'

    for(i=0;i<s;i++)
    {
        switch(flag)//flag shows where to put border
        {
            case 0: border = SIZE -i;  break;
            case 1: border = i+1;      break;
            case 2: border = SIZE -i-1;break;
            case 3: border = i;        break;

        }
        for(j=0;j<s;j++)
        {
            printf("%c",j<border? c1: c2);//pay attention to border!
        }
        printf("\n");
    }

}