Submission #241377

#	Time	Username	Problem	Language	Result	Execution time	Memory
241377		Mercenary	K blocks (IZhO14_blocks)	C++14	100 / 100	196 ms	41832 KiB

blocks

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/trie_policy.hpp>

#define pb push_back
#define mp make_pair
#define taskname "A"

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef tree <int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

const int maxn = 1e5 + 5;
const int maxk = 1e2 + 1;

const int logn = log2(maxn) + 1;
int dp[101][maxn];
int n , k , a[maxn];
int dp1[maxn];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    fill_n(&dp[0][0],maxn*maxk,1e9);
    dp[1][0] = 0;
    cin >> n >> k;
    for(int i = 1 ; i <= n ; ++i){
        cin >> a[i];
        dp[1][i] = max(dp[1][i - 1] , a[i]);
    }
    dp[1][0] = 1e9;
    for(int i = 2 ; i <= k ; ++i){
        vector<int> s;
        for(int j = 1 ; j <= n ; ++j){
            int tmp = dp[i - 1][j - 1];
            while(s.size() && a[s.back()] <= a[j]){
                tmp = min(tmp , dp1[s.back()]);
                s.pop_back();
            }
            dp1[j] = tmp;
            dp[i][j] = tmp + a[j];
            if(s.size())dp[i][j] = min(dp[i][j] , dp[i][s.back()]);
            s.pb(j);
//            cout << dp[i][j] << " ";
        }
    }
    cout << dp[k][n];
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:30:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:31:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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