Recurrence of a triangle (hdu1249) and a triangle hdu1249

Recurrence of a triangle (hdu1249) and a triangle hdu1249
Triangle

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission (s): 5598 Accepted Submission (s): 3816

Problem Description how many areas can a plane be divided into with N triangles at most?

 

The first line of Input data is a positive integer T (1 <= T <= 10000), indicating the number of test data. then there is the T group of test data, each group of test data contains only one positive integer N (1 <= N <= 10000 ).

 

Output for each group of test data, please Output the results required in the question.

 

Sample Input212

 

Sample Output28 train of thought: You can figure it yourself. The rule I found is: each edge of each newly added triangle overlaps two existing sides of each triangle. [(n-1) * 2-1] * 3 + 3 = 6 * (n-1) reprinted please indicate the source: Looking for and star child questions link: http://acm.hdu.edu.cn/showproblem.php? Pid = 1, 1249

#include<stdio.h>#define LL __int64LL ans[10005];void init(){    ans[0]=1;    ans[1]=2;    ans[2]=8;    for(int i=3;i<=10000;i++)    {        //(2*(n-1)-1)*3+3=6*(n-1)        ans[i]=ans[i-1]+6*(i-1);    }}int main(){    int n,T;    init();    scanf("%d",&T);    while(T--)    {        scanf("%d",&n);        printf("%I64d\n",ans[n]);    }    return 0;}