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#include<stdio.h>
#include<math.h>

const PI 3.1415926

main()
{
    double x, y,radious,area;
    int year;
    int n,i = 1;
    
    while(n--)     //计算n多次
    {
    scanf("%lf%lf", &x, &y);
    radious = x * x + y * y;
    area = PI * radious /2.0;
    year = (int)ceil(area / 50.0);
    
    printf("This property will begin eroding in year %d.\n", year);
    }
    printf("End of output.\n");
}