Submission #137861

#	Time	Username	Problem	Language	Result	Execution time	Memory
137861		zoooma13	Cake 3 (JOI19_cake3)	C++14	0 / 100	33 ms	31736 KiB

cake3

#include <bits/stdc++.h>
using namespace std;

#define MAX_N 2003
#define INF 0x3f3f3f3f3f3f3f3f

int n ,m;
int c[MAX_N] ,v[MAX_N];

long long dp[MAX_N][MAX_N];
long long solve(int p ,int l){
    if(p == n)
        return -INF;
    auto&ret = dp[p][l];
    if(~ret)
        return ret;

    if(l == 1)
        return ret = max(-2LL*c[p]+v[p] ,solve(p+1 ,l));
    return ret = max(v[p]+solve(p+1 ,l-1) ,solve(p+1 ,l));
}

int main()
{
    scanf("%d%d",&n,&m);
    for(int i=0; i<n; i++)
        scanf("%d%d",&v[i],&c[i]);

    vector <int> ord(n);
    iota(ord.begin() ,ord.end() ,0);
    sort(ord.begin() ,ord.end() ,[](int&i ,int&j){
        return c[i] < c[j];
    });
    vector <int> V(n) ,C(n);
    for(int i=0; i<n; i++)
        V[i] = v[ord[i]] ,C[i] = c[ord[i]];
    for(int i=0; i<n; i++)
        v[i] = V[i] ,c[i] = C[i];

    memset(dp ,-1 ,sizeof dp);
    long long ans = 0LL;
    for(int i=0; i<=n-m; i++)
        ans = max(ans ,solve(i+1 ,m-1)+v[i]+2*c[i]);
    printf("%lld\n",ans);
}

Compilation message (stderr)

cake3.cpp: In function 'int main()':
cake3.cpp:25:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~
cake3.cpp:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&v[i],&c[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 19
• Subtask 3: 0 / 76