Submission #51430

#	Time	Username	Problem	Language	Result	Execution time	Memory
51430		Flying_dragon_02	Watching (JOI13_watching)	C++14	100 / 100	448 ms	32252 KiB

watching

#include<bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define mp make_pair

typedef pair<int,int> ii;

long long l,r,n,p,q,dp[2005][2005],nxt[2005][3],a[2005];
vector<long long> vec;

bool check(long long w){
    a[n+1] = a[n];
    for(int i = 0;i<=n+1;i++){
        for(int j = 0;j<=1;j++){
            long long cost;
            if(j == 0)
                cost = w-1;
            else
                cost = 2*w-1;
            int it = upper_bound(vec.begin(),vec.end(),a[i]+cost) - vec.begin() - 1;
            nxt[i][j] = it;
        }
    }

    memset(dp,0,sizeof(dp));
    for(int i = 0;i<=p;i++){
        for(int j = 0;j<=q;j++){
            if(i>=1)
                dp[i][j] = nxt[dp[i-1][j]+1][0];
            if(j>=1)
                dp[i][j] = max(dp[i][j],nxt[dp[i][j-1]+1][1]);
        }
    }
    if(dp[p][q]>=n)
        return 1;
    else
        return 0;
}
int main(){
    cin.tie(0),ios::sync_with_stdio(0);
    cin >> n >> p >> q;
    for(int i = 1;i<=n;i++){
        cin>>a[i];
        vec.pb(a[i]);
    }
    sort(a+1,a+1+n);
    vec.pb(-1);
    sort(vec.begin(),vec.end());
    if(p+q>=n){
        cout<<"1\n";
        return 0;
    }
    l = 1;
    r = 1e9;
    while(l<r){
        long long mid = (l+r)/2;
        if(check(mid))
            r = mid;
        else
            l = mid+1;
    }
    cout<<l;
}

• Subtask 1: 50 / 50
• Subtask 2: 50 / 50