ACM (6) 喷水装置（一）

//http://acm.nyist.net/JudgeOnline/problem.php?pid=6
#include<stdio.h>
#include<math.h>

int main(){
freopen("input.txt", "r", stdin);

int m;
scanf("%d", &m);
while (m--){
int N;
double r[601];
double temp;

scanf("%d", &N);
for (int i = 0; i < N; i++){
scanf("%lf", &r[i]);
}

for (int i = 0; i < N-1; i++){
int k = i;
for (int j = i + 1; j < N; j++){
if (r[k]<r[j]){
k = j;
}
}
if (k != i){
temp = r[i];
r[i] = r[k];
r[k] = temp;
}
}

double l = 0;
for (int i = 0; i < N; i++){
l = l+ 2*(sqrt(r[i] * r[i] - 1));
if (l >= 20){
printf("%d\n", i + 1);
break;
}
}

}
}