A. ACM ICPC
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output
In a small but very proud high school it was decided to win ACM ICPC. This goal requires to compose as many teams of three as possible, but since there were only 6 students who wished to participate, the decision was to build exactly two teams.
After practice competition, participant number i got a score of ai. Team score is defined as sum of scores of its participants. High school management is interested if it's possible to build two teams with equal scores. Your task is to answer that question.
Input
The single line contains six integers a1, ..., a6 (0 ≤ ai ≤ 1000) — scores of the participants
Output
Print "YES" (quotes for clarity), if it is possible to build teams with equal score, and "NO" otherwise.
You can print each character either upper- or lowercase ("YeS" and "yes" are valid when the answer is "YES").
Examples
Input
Copy
1 3 2 1 2 1
Output
Copy
YES
Input
Copy
1 1 1 1 1 99
Output
Copy
NO
Note
In the first sample, first team can be composed of 1st, 2nd and 6th participant, second — of 3rd, 4th and 5th: team scores are 1 + 3 + 1 = 2 + 1 + 2 = 5.
In the second sample, score of participant number 6 is too high: his team score will be definitely greater.
题目链接：http://codeforces.com/contest/890/problem/A
题意：有六个分数，求是否存在三个分数和等于总和的一半。水题，直接三重循环暴力。
#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int main()
{
int sum = 0;
int a[6];
for(int i = 0; i < 6; i++)
{
cin >> a[i];
sum += a[i];
}
for(int i = 0; i < 6; i++)
for(int j = 0; j < 6; j++)
{
if(j == i)
continue;
else
{
for(int k = 0; k < 6; k++)
{
int ans = 0;
if(k == j || k == i)
continue;
else
ans = a[i] + a[j] + a[k];
if(2*ans == sum)
{
puts("YES");
return 0;
}
}
}
}
puts("NO");
return 0;
}