oj.uz

Submission #145188

# Submission time Handle Problem Language Result Execution time Memory
145188 2019-08-19T08:37:51 Z solimm4sks Watching (JOI13_watching) C++14
0 / 100
 495 ms 31872 KB 
#include <bits/stdc++.h>
using namespace std;

long long n, p, q;
long long a[200005];
long long dp[2005][2005];

long long smallReach[2005];
long long bigReach[2005];

#define INF 1000000

bool check(long long w){
    for(long long i = 0; i <= n; ++i){
        for(long long j = 0; j <= n; ++j){
            dp[i][j] = INF;
        }
    }

    /*
    for(int i = 1; i <= n; ++i){
        for(int j = i; j > 0; --j){
            if(a[i] - a[j] + 1 <= w)smallReach[i] = j;
            if(a[i] - a[j] + 1 <= 2 * w)bigReach[i] = j;
        }
    }
    */

    for(int i = 1; i <= n; i++) {
        for(int j = i - 1; j >= 0; j--) {
            if(w <= a[i] - a[j] && w > a[i] - a[j + 1]) smallReach[i] = j + 1;
            if(2 * w <= a[i] - a[j] && 2 * w > a[i] - a[j + 1]) bigReach[i] = j + 1;
        }
    }

    for(long long i = 0; i <= n; ++i){
        dp[0][i] = 0;
    }

    for(long long i = 1; i <= n; ++i){
        for(long long j = 0; j <= n; ++j){
            if(j){
                dp[i][j] = min(dp[bigReach[i] - 1][j] + 1, dp[smallReach[i] - 1][j - 1]);
            }else{
                dp[i][0] = dp[bigReach[i] - 1][0] + 1;
            }
        }
    }

    if(dp[n][p] <= q){
        return true;
    }
    return false;
}


int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> n >> p >> q;
    for(long long i = 1; i <= n; ++i){
        cin >> a[i];
    }

    sort(a + 1, a + n + 1);

    p = min(p, n);
    q = min(q, n);

    long long l = 0;
    long long r = 1000000010;
    long long lc = -1;
    while(l <= r){
        long long mid = (l + r) / 2;
        bool ch = check(mid);
        if(ch){
            r = mid - 1;
            lc = mid;
        }else{
            l = mid + 1;
        }
    }

    if(lc == -1){
        while(1);
    }

    cout << lc << "\n";
    return 0;
}

Subtask #1
0 / 50.0

# Verdict Execution time Memory Grader output
1 Incorrect 4 ms 888 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Incorrect 495 ms 31872 KB Output isn't correct
2 Halted 0 ms 0 KB -