A. Cut Ribbon:题目地址

题意：一条长为n的彩带切割，切割后每段长度是a或者是b或者是c

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
vector<int> a((int)4e5);
vector<int> b((int)4e5);
int main()
{int n,a,b,c;cin>>n>>a>>b>>c;int aa = n/a;int bb = n/b;int cc = n/c;int res = 0;for (int i=0;i<=aa;i++){for (int j=0;j<=bb;j++){int sum = i*a+j*b;if (sum<=n){if ((n-sum)%c==0){res=max(res,(n-sum)/c+i+j);}}}}cout<<res<<endl;
}