C - I Think I Need a Houseboat

C - I Think I Need a Houseboat

题目描述：

Fred Mapper is considering purchasing some land in Louisiana to build his house on. In the process of investigating the land, he learned that the state of Louisiana is actually shrinking by 50 square miles each year, due to erosion caused by the Mississippi River. Since Fred is hoping to live in this house the rest of his life, he needs to know if his land is going to be lost to erosion.

After doing more research, Fred has learned that the land that is being lost forms a semicircle. This semicircle is part of a circle centered at (0,0), with the line that bisects the circle being the X axis. Locations below the X axis are in the water. The semicircle has an area of 0 at the beginning of year 1. (Semicircle illustrated in the Figure.)

输入格式：

The first line of input will be a positive integer indicating how many data sets will be included (N). Each of the next N lines will contain the X and Y Cartesian coordinates of the land Fred is considering. These will be floating point numbers measured in miles. The Y coordinate will be non-negative. (0,0) will not be given.

输出格式：

For each data set, a single line of output should appear. This line should take the form of: “Property N: This property will begin eroding in year Z.” Where N is the data set (counting from 1), and Z is the first year (start from 1) this property will be within the semicircle AT THE END OF YEAR Z. Z must be an integer. After the last data set, this should print out “END OF OUTPUT.”

输入与输出样例：

思路分析：

这道题特么的就是找半径，然后用公式（3.14rr）/100求出年份，当求出的值大于所输入的值，就减去1，当相等就输出即可。

代码：

#include<stdio.h>
#include<math.h>
double lemon(double c,double d)
{
	return (c*c+d*d);
}
int main()
{
	int a,e=1,h;
	double b[10000],c,d;
	scanf("%d",&a);
	while(a--)
	{
		scanf("%lf %lf",&c,&d);
		b[e]=3.14*lemon(c,d)/100.00;
		e++;
	}
	for(a=1;a<=e-1;a++)
	{
		if(b[a]-(int)b[a]>0)
		{
			h=(int)b[a]+1;
		}
		else
		h=(int)b[a];
		printf("Property %d: This property will begin eroding in year %d.\n",a,h);
	}
	printf("END OF OUTPUT.");
}