cf 1341D Nastya and Scoreboard

题目

题目链接：https://codeforces.com/contest/1341/problem/D

思路

dp[i][j]表示到第i个数字时还剩j个棍子能拼给出的最大的数

代码

#include<cstdio>
#include<cstring>
#include<cmath>
#include<cstdlib>
#include<cctype>
#include<ctime>
#include<iostream>
#include<string>
#include<map>
#include<queue>
#include<stack>
#include<set>
#include<vector>
#include<iomanip>
#include<list>
#include<bitset>
#include<sstream>
#include<fstream>
#include<complex>
#include<algorithm>
#include<bitset> 
#if __cplusplus >= 201103L
#include <unordered_map>
#include <unordered_set>
#endif
#define ll long long
using namespace std;
const int INF = 0x3f3f3f3f;
string s[10]={"1110111", "0010010", "1011101", "1011011", "0111010", "1101011", "1101111", "1010010", "1111111", "1111011"};
vector<bitset<7>> v;
vector<pair<int,int>> num[4000];
int dp[4000][4000],last[4000][4000];
int main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	for(int i=0;i<=9;i++){
		v.push_back(bitset<7>(s[i]));
	}
	int n,k;
	cin>>n>>k;
	for(int i=1;i<=n;i++){
		string s1;
		cin>>s1;
		bitset<7> bi(s1);
		for(int j=0;j<v.size();j++){
			auto &ds=v[j];
			if((bi&ds)!=bi) continue;
            num[i].push_back(make_pair(ds.count() - bi.count(), j + 1));
		}
	}
	for(auto i:num[n]){
		dp[n][i.first]=max(dp[n][i.first],i.second);
	}
	for(int i=n-1;i>=1;i--){
		for(int j=0;j<=k;j++){
			for(auto t:num[i]){
				if(j<t.first) continue;
				if(dp[i+1][j-t.first]&&dp[i][j]<t.second){
					dp[i][j]=t.second;
					last[i][j]=j-t.first;
				}
			}
		}
	}
	if(dp[1][k]==0) cout<<"-1"<<endl;
	else{
		int p1=1,p2=k;
		while(p1<=n){
			cout<<dp[p1][p2]-1;
			p2=last[p1][p2];
			p1++;
		}
	} 
    return 0;
}