oj.uz

답안 #875624

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
875624 2023-11-20T08:33:40 Z josanneo22 Islands (IOI08_islands) C++17
100 / 100
 263 ms 53408 KB 
/*
Problem: P4381 [IOI2008] Island
When:    2023-11-19 19:41:26
Author:  Ning07
*/

#include<bits/stdc++.h>
using namespace std;
using i64 = long long;

const int NN=2e6;
int N, A[NN], deg[NN];
i64 ans, f[NN], g[NN], W[NN];
i64 get(int p){
    int st=p; p=A[p];
    i64 m1=f[st],m2=f[st];
    i64 s=W[st],ans1=g[st],ans2=-1E18;
    while (p != st) {
        deg[p] = 0;
        ans1=max(ans1,max(g[p],f[p]+s+m1)); 
        ans2=max(ans2,f[p]-s+m2);
        m1=max(m1,f[p]-s),m2=max(m2,f[p]+s);
        s+=W[p],p=A[p];
    }
    return max(ans1,ans2+s);
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);

    cin>>N;
    for(int i=1;i<=N;i++){
        cin>>A[i]>>W[i]; 
        ++deg[A[i]];
    }
    queue<int> q;
    for(int i=1;i<=N;i++)
        if (!deg[i]) 
            q.push(i);

    while (!q.empty()){
        int p=q.front(); q.pop();
        i64 c=f[p]+W[p];
        g[A[p]]=max(g[A[p]],max(f[A[p]]+c,g[p]));
        f[A[p]]=max(f[A[p]],c);
        if (!--deg[A[p]]) q.push(A[p]);
    }

    for(int i=1;i<=N;i++)
        if (deg[i]) 
            ans += get(i);
    cout<<ans<<'\n';
}

Subtask #1
33.0 / 33.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct
6 Correct 1 ms 4456 KB Output is correct
7 Correct 1 ms 4444 KB Output is correct
8 Correct 1 ms 4704 KB Output is correct
9 Correct 1 ms 4444 KB Output is correct
10 Correct 1 ms 4560 KB Output is correct
11 Correct 1 ms 4444 KB Output is correct

Subtask #2
3.0 / 3.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct

Subtask #3
4.0 / 4.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4700 KB Output is correct

Subtask #4
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4956 KB Output is correct
2 Correct 6 ms 7772 KB Output is correct
3 Correct 7 ms 5212 KB Output is correct
4 Correct 2 ms 4956 KB Output is correct

Subtask #5
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 9 ms 8284 KB Output is correct
2 Correct 15 ms 9064 KB Output is correct

Subtask #6
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 29 ms 14720 KB Output is correct
2 Correct 27 ms 14460 KB Output is correct
3 Correct 39 ms 18772 KB Output is correct

Subtask #7
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 55 ms 23628 KB Output is correct
2 Correct 72 ms 27256 KB Output is correct
3 Correct 66 ms 21844 KB Output is correct
4 Correct 96 ms 37460 KB Output is correct

Subtask #8
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 145 ms 37128 KB Output is correct
2 Correct 154 ms 44088 KB Output is correct
3 Correct 113 ms 42620 KB Output is correct
4 Correct 148 ms 51188 KB Output is correct
5 Correct 140 ms 50952 KB Output is correct
6 Correct 263 ms 52532 KB Output is correct
7 Correct 156 ms 53408 KB Output is correct

Subtask #9
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 149 ms 52048 KB Output is correct
2 Correct 162 ms 52080 KB Output is correct
3 Correct 139 ms 36692 KB Output is correct
4 Correct 135 ms 36128 KB Output is correct
5 Correct 149 ms 51356 KB Output is correct
6 Correct 154 ms 50772 KB Output is correct
7 Correct 202 ms 52820 KB Output is correct