Submission #881189

#	Time	Username	Problem	Language	Result	Execution time	Memory
881189		JakobZorz	Knapsack (NOI18_knapsack)	C++14	100 / 100	160 ms	247260 KiB

knapsack

#include<iostream>
#include<vector>
#include<queue>
#include<stack>
#include<algorithm>
#include<limits.h>
#include<math.h>
#include<map>
#include<set>
#include<unordered_map>
#include<unordered_set>
#include<iomanip>
#include<cstring>
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using namespace std;
//const int MOD=1e9+7;
//typedef pair<ll,ll>Point;
//typedef pair<ll,ll>Line;
//#define x first
//#define y second
 
ll knapsack(vector<pair<int,int>>arr,int s){ // (weight, reward)
    vector<vector<ll>>dp(arr.size()+1,vector<ll>(s+1)); // dp[i][j] = if we take first i elements, how much can we take with j space left
    
    for(int i=1;i<=arr.size();i++){
        for(int j=0;j<=s;j++){
            dp[i][j]=dp[i-1][j];
            if(j-arr[i-1].first>=0){
                dp[i][j]=max(dp[i][j],dp[i-1][j-arr[i-1].first]+arr[i-1].second);
            }
        }
    }
    return dp[(int)arr.size()][s];
}
 
void solve(){
    int s,n;
    cin>>s>>n;
    vector<vector<pair<int,int>>>arr(2001);
    for(int i=0;i<n;i++){
        int w,r,c;
        cin>>r>>w>>c;
        arr[w].emplace_back(r,c);
    }
    
    vector<pair<int,int>>arr2;
    for(int i=1;i<2001;i++){
        sort(arr[i].begin(),arr[i].end());
        reverse(arr[i].begin(),arr[i].end());
        int rem=s/i;
        for(auto j:arr[i]){
            while(j.second&&rem){
                arr2.emplace_back(i,j.first);
                j.second--;
                rem--;
            }
            if(rem==0)
                break;
        }
    }
    
    cout<<knapsack(arr2,s)<<"\n";
}

int main(){
    ios::sync_with_stdio(false);cout.tie(NULL);cin.tie(NULL);
    //freopen("bank.in","r",stdin);freopen("bank.out","w",stdout);
    int t=1;//cin>>t;
    while(t--)solve();
    return 0;
}
 
/*
 
15 5
4 12 1
2 1 1
10 4 1
1 1 1
2 2 1
 
15
 
20 3
5000 15 1
100 1 3
50 1 4
 
5400
 
 */

Compilation message (stderr)

knapsack.cpp: In function 'll knapsack(std::vector<std::pair<int, int> >, int)':
knapsack.cpp:27:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |     for(int i=1;i<=arr.size();i++){
      |                 ~^~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 27 / 27