#include<stdio.h>
#include<math.h>
bool isIntersect(int x, int y)
{
    int r1 = 2, c1 = 0, r2 = 1, c2 = 3;

    if ((x - r1) * (x - r2) > 0 || (y - c1) * (y - c2) > 0)
        return false;

    float slope = (r1 - r2) / (float)(c1 - c2);
    float sum = slope * (y - c1) + r1 - x;
    sum = sum > 0 ? sum : -sum;

    if (sum / sqrt(1 + pow(slope, 2)) > 0.5) return false;

    return true;
}
int main()
{
    for (int i = 0; i < 4; ++i)
        for (int j = 0; j < 4; ++j)
            printf("i:%d,j:%d  rst:%d\n", i, j, isIntersect(i, j));

    return 0;
}