POJ-1005

#include <stdio.h>
#include <math.h>
#define PI 3.1415926
int get_year(double x, double y);

int main(void) {
    int n;
    int i = 0;
    double x, y;
    
    scanf("%d", &n);
    while (i < n) {
        i++;
        scanf("%lf%lf", &x, &y);
        printf("Property %d: This property will begin eroding in year %d.
",
            i, get_year(x, y));
    } 
    printf("END OF OUTPUT.
");
    
    return 0;
}

int get_year(double x, double y) {
    int i = 0;
    double r = 0.0;
    double s = 0.0;
    double v = x * x + y * y;
    
    while (v > r * r) {
        s += 50;
        r = sqrt(2 * s / PI);       
        i++;
    }
    
    return i;
}