Submission #330027

#	Time	Username	Problem	Language	Result	Execution time	Memory
330027		oak	Knapsack (NOI18_knapsack)	C++14	29 / 100	2 ms	364 KiB

knapsack

#include<bits/stdc++.h>
using namespace std;
pair<long long,int> dp[2][2020];
int main(){
	int n,k,s,i,j;
	scanf("%d %d",&s,&n);
	int wei[n],num[n];
	long long val[n];
	for(i=0;i<n;i++){
		scanf("%lld %d %d",&val[i],&wei[i],&num[i]);
	}
	/*for(i=1;i<=s;i++){
		printf("%d\t",i);
	}printf("\n");*/
	for(i=0;i<n;i++){
		for(j=1;j<=s;j++){
			dp[i%2][j] = make_pair(dp[(i+1)%2][j].first*1ll,num[i]);
			if(j>=wei[i] && dp[(i+1)%2][j-wei[i]].first*1ll + val[i]*1ll > dp[i%2][j].first*1ll){
				dp[i%2][j] = make_pair(dp[(i+1)%2][j-wei[i]].first*1ll + val[i]*1ll,num[i]-1);
			}
			if(j>=wei[i] && dp[i%2][j-wei[i]].second && dp[i%2][j-wei[i]].first*1ll + val[i]*1ll > dp[i%2][j].first*1ll){
				dp[i%2][j] = make_pair(dp[i%2][j-wei[i]].first*1ll + val[i]*1ll,dp[i%2][j-wei[i]].second - 1);
			}
			if(j>=wei[i] && !dp[i%2][j-wei[i]].second && dp[i%2][j-wei[i]].first*1ll > dp[i%2][j].first*1ll){
				dp[i%2][j] = dp[i%2][j-wei[i]];
			}
			if(dp[i%2][j-1] > dp[i%2][j]){
				dp[i%2][j] = dp[i%2][j-1];
			}
			//printf("%d,%d\t",dp[i%2][j].first,dp[i%2][j].second);
		}//printf("\n");
	}
	printf("%lld",dp[(i-1)%2][s].first);
}
/*
15 4
5 3 1
6 4 2
3 2 3
6 1 4
*/

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:5:8: warning: unused variable 'k' [-Wunused-variable]
    5 |  int n,k,s,i,j;
      |        ^
knapsack.cpp:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d %d",&s,&n);
      |  ~~~~~^~~~~~~~~~~~~~~
knapsack.cpp:10:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%lld %d %d",&val[i],&wei[i],&num[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 0 / 20
• Subtask 4: 0 / 24
• Subtask 5: 0 / 27