oj.uz

Submission #239234

# Submission time Handle Problem Language Result Execution time Memory
239234 2020-06-14T22:24:22 Z aggu_01000101 Watching (JOI13_watching) C++14
100 / 100
 72 ms 7928 KB 
#include <bits/stdc++.h>
#define int long long
#define INF 1000000000000000
#define lchild(i) (i*2 + 1)
#define rchild(i) (i*2 + 2)
#define mid(l, u) ((l+u)/2)
#define x(p) p.first
#define y(p) p.second
#define MOD 998244353
using namespace std;
int n, p, q;
vector<int> v;
int ct[2005][2];
int makect(int w){
    for(int i = 1;i<=n;i++){
        auto it = lower_bound(v.begin(), v.end(), v[i] + w);
        it--;
        int ind = it - v.begin();
        ct[i][0] = ind;
        it = lower_bound(v.begin(), v.end(), v[i] + w + w);
        it--;
        ind = it - v.begin();
        ct[i][1] = ind;
    }
}
bool f(int w){
    makect(w);
    int dp[p+1][q+1];
    dp[0][0] = 0;
    for(int i = 0;i<=p;i++){
        for(int j = 0;j<=q;j++){
            if(i==0 && j==0) continue;
            dp[i][j] = -INF;
            if(i>0){
                dp[i][j] = max(dp[i][j], ct[dp[i-1][j]+1][0]);
            }
            if(j>0){
                dp[i][j] = max(dp[i][j], ct[dp[i][j-1]+1][1]);
            }
            if(dp[i][j] == n) return true;
        }
    }
    return false;
}
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    cin>>n>>p>>q;
    int a[n];
    for(int i = 0;i<n;i++) cin>>a[i];
    sort(a, a+n);
    v.push_back(-1);
    for(int i = 0;i<n;i++) v.push_back(a[i]);
    p = min(p, n);
    q = min(q, n);
    int l = 1;
    int u = 1e9;
    int ans = 1e9;
    while(l<=u){
        int mid = mid(l, u);
        bool cando = f(mid);
        if(cando){
            ans = min(ans, mid);
            u = mid - 1;
        }
        else l = mid + 1;
    }
    cout<<ans<<"\n";
}

Compilation message

watching.cpp: In function 'long long int makect(long long int)':
watching.cpp:25:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 5 ms 384 KB Output is correct
4 Correct 5 ms 416 KB Output is correct
5 Correct 5 ms 384 KB Output is correct
6 Correct 5 ms 384 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 6 ms 384 KB Output is correct
12 Correct 5 ms 384 KB Output is correct
13 Correct 5 ms 384 KB Output is correct
14 Correct 6 ms 384 KB Output is correct
15 Correct 6 ms 384 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 37 ms 6016 KB Output is correct
4 Correct 20 ms 1536 KB Output is correct
5 Correct 10 ms 384 KB Output is correct
6 Correct 10 ms 512 KB Output is correct
7 Correct 10 ms 384 KB Output is correct
8 Correct 17 ms 1152 KB Output is correct
9 Correct 18 ms 1152 KB Output is correct
10 Correct 25 ms 1792 KB Output is correct
11 Correct 16 ms 1792 KB Output is correct
12 Correct 72 ms 7928 KB Output is correct
13 Correct 10 ms 512 KB Output is correct
14 Correct 10 ms 512 KB Output is correct
15 Correct 11 ms 384 KB Output is correct