Educational Codeforces Round 112 (Rated for Div. 2)
A
我写的挺烦的，其实判断一下奇偶数和有没有a>0就行

    #include <bits/stdc++.h>using namespace std;#define int long longsigned main(){int t;cin>>t;while (t--){int n;cin>>n;int a = n/6;n%=6;int cou = a*6;if (n==0){}else if (n==1) {if (a>0) cou+=2;else cou+=6;}else if (n==2) {if (a>0) cou+=2;else cou+=6;}else if (n==3) {if (a>0) cou+=4;else cou+=6;}else if (n==4) {if (a>0) cou+=4;else cou+=6;}else if (n==5){cou+=6;}cou=cou/2*5;cout<<cou<<endl;}}

B
题目输出要求就是迷惑人的

#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main()
{int t;cin >> t;while (t--){int w, h;cin >> w >> h;int x1, y1, x2, y2;cin >> x1 >> y1 >> x2 >> y2;int a, b;cin >> a >> b;int chax = w - (x2 - x1), chay = h - (y2 - y1);if (a > chax && b > chay)cout << -1 << endl;else{int mx = max(x1, w - x2);int my = max(y1, h - y2);int cou;if (a <= chax && b <= chay){cou = min(a - mx,b - my);cou = max((int)0,cou);}else if (a<=chax){cou = max(a - mx , (int)0);}else{cou = max((int)0,b - my);}cout << cou << ".000000000" << endl;}}
}

C
我一开始以为是DP什么的，结果发现贼简单的一道题，没啥意思。

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 100010;
int ch[3][N];
signed main()
{int t;cin>>t;while (t--){int n,sum=0;cin>>n;for (int i=1;i<3;i++){for (int j=1;j<=n;j++){cin>>ch[i][j];if (i==1) sum+=ch[i][j];}}int cou = 0x3f3f3f3f;int sum1 = 0;for (int i=1;i<=n;i++){sum1+=ch[2][i-1];sum-=ch[1][i];sum = max(sum,sum1);cou = min(cou,sum);}cout<<cou<<endl;}
}