got WA for test#1. Plz. help me.

#include<stdio.h>
float power(float i,float j)
{
    float l,sum = 1;
    if (i == 0)
        return 0;
    if (j == 0)
        return 1;
    for(l = 1;l<= j;l++)
        sum  = (sum * i);
    return (sum);
}
int main()
{
    int N,i,j;
    float x[110],y[110],R,
    sum = 0,pi=3.14159265358979323846;
    float b[110];
    scanf("%d",&N);
    scanf("%f",&R);
    for (i=0;i<N;i++)
    {
        scanf("%f %f",&x[i],&y[i]);
    }
    j = 1;
    for (i=0;i<N;i++)
    {
        if (i == (N-1))
        {
            b[i] = sqrt((power(fabs((x[0]) - (x[i])),2)) +
                        (power(fabs((y[0]) - (y[i])),2)));
        }
        else
        {
            b[i] = sqrt((power(fabs((x[i+1]) - (x[i])),2))+
                      (power(fabs((y[i+1]) - (y[i])),2)));
        }
    }
    for (i = 0;i<N;i++)
    {
        sum = sum + b[i];
    }
    sum = sum + (2*pi*R);
    printf("%.2f",sum);
    return 0;
}

Edited by author 03.09.2008 20:29

Edited by author 03.09.2008 20:34