hdoj KK's Point 5621 （数学&规律）

KK's Point

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 805    Accepted Submission(s): 270

Problem Description

Our lovely KK has a difficult mathematical problem:He points N(2≤N≤105) points on a circle,there are all different.Now he's going to connect the N points with each other(There are no three lines in the circle to hand over a point.).KK wants to know how many points are there in the picture(Including the dots of boundary).

 

Input

The first line of the input file contains an integer T(1≤T≤10), which indicates the number of test cases.

For each test case, there are one lines,includes a integer N(2≤N≤105),indicating the number of dots of the polygon.

 

Output

For each test case, there are one lines,includes a integer,indicating the number of the dots.

 

Sample Input

234

 

Sample Output

35
//因为题中说任意三条直线不相交，所以只要求出给出的点可以组成几个四边形就可以了。
#include<stdio.h>#include<string.h>#include<algorithm>#include<iostream>#define INF 0x3f3f3f3f#define N 10010using namespace std;int main(){int t;scanf("%d",&t);while(t--){unsigned long long n;scanf("%llu",&n);if(n<4)printf("%llu\n",n);else{unsigned long long s=n*(n-1)/2*(n-2)/3*(n-3)/4+n;printf("%llu\n",s);}}return 0;}