#include <stdio.h>

void main(void){
	int t = 0;
	scanf("%d",&t);
	double triangleList[t];
	for(int i = 0 ; i < t ; i++){
		scanf("%le",triangleList[i]);
		triangleList[i] = 1.299038105676657 * triangleList[i] * triangleList[i];
	}
	for(int i = 0 ; i < t ; i++){
		scanf("%0.12f",triangleList[i]);
	}
}