Submission #1312594

#	Time	Username	Problem	Language	Result	Execution time	Memory
1312594		zangdo	K blocks (IZhO14_blocks)	C++20	0 / 100	1 ms	792 KiB

blocks

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#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 +5;
const int MAXK = 105;
int arr[MAXN] ,pos[MAXN],n,k;
long long dp[MAXN][MAXK], pref[MAXN];
stack <int> gay;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);
    freopen("blocks.in", "r", stdin);
    freopen("blocks.out", "w", stdout);
    cin>>n>>k;
    for(int i=1; i<=n;i++) {cin>>arr[i]; pref[i]=pref[i-1]+arr[i];}
    for(int i=n; i>=1; i--){
        while(!gay.empty()){
            if(arr[i]>arr[gay.top()]) {pos[gay.top()]= i;gay.pop();} 
            else break;
        }
        gay.push(i);
    }
    for (int i=1; i<=n;i++){
        for(int j=1; j<=k;j++){
            if(i<j) break;
            if(pos[i]<j-1) dp[i][j]= pref[j-1]+arr[i];
            else dp[i][j]= dp[pos[i]][j] + arr[i];
        }
    }
    //cout<<arr[1]<<endl;
    cout<<dp[n][k];
    return 0;
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:21:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |     freopen("blocks.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:22:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     freopen("blocks.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 18
• Subtask 3: 0 / 21
• Subtask 4: 0 / 47