oj.uz

Submission #524873

# Submission time Handle Problem Language Result Execution time Memory
524873 2022-02-10T07:42:43 Z qwerasdfzxcl Mountains and Valleys (CCO20_day1problem3) C++14
3 / 25
 12 ms 12748 KB 
#include <bits/stdc++.h>

typedef long long ll;
using namespace std;
struct Edge{
    int v, w, i;
    Edge(){}
    Edge(int _v, int _w, int _i): v(_v), w(_w), i(_i) {}
};
vector<Edge> adj[500500];
int on[2002000], W[2002000], dist[500500];
vector<Edge> E;

vector<int> P;
bool dfs0(int s, int e, int pa = -1){
    if (s==e) return 1;
    for (auto &v:adj[s]) if (v.v!=pa && on[v.i]){
        P.push_back(v.i);
        if (dfs0(v.v, e, s)) return 1;
        P.pop_back();
    }
    return 0;
}

void dfs(int s, int pa = -1, int w = 0){
    if (pa==-1) dist[s] = 0;
    else dist[s] = dist[pa] + w;
    for (auto &v:adj[s]) if (v.v!=pa && on[v.i]) dfs(v.v, s, v.w);
}

int cur = 0, ans = 1e9, m;
void calc(int n){
    dfs(0);
    dfs(max_element(dist, dist+n)-dist);

    ans = min(ans, cur*2 - *max_element(dist, dist+n));

    //printf("cur: %d, ans = %d\n", cur, cur*2 - *max_element(dist, dist+n));
    //for (int i=1;i<=m;i++) printf("%d ", on[i]);
    //printf("\n");
}

int main(){
    int n;
    scanf("%d %d", &n, &m);
    for (int i=1;i<=m;i++){
        int x, y, z;
        scanf("%d %d %d", &x, &y, &z);
        adj[x].emplace_back(y, z, i);
        adj[y].emplace_back(x, z, i);
        W[i] = z;

        if (z==1) on[i] = 1, cur++;
        else E.emplace_back(x, y, i);
    }

    calc(n);
    if (n>500) {printf("%d\n", ans); return 0;}

    for (auto &e:E){
        P.clear();
        assert(dfs0(e.v, e.w));
        //printf("%d %d: ", e.v, e.w);
        //for (auto &x:P) printf("%d ", x);
        //printf("\n");

        on[e.i] = 1, cur += W[e.i];

        for (auto &x:P){
            on[x] = 0, cur -= W[x];
            calc(n);
            on[x] = 1, cur += W[x];
        }

        on[e.i] = 0, cur -= W[e.i];
    }

    printf("%d\n", ans);
    return 0;
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:45:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:48:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         scanf("%d %d %d", &x, &y, &z);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
1.0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct

Subtask #2
0.0 / 2.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct
16 Correct 9 ms 11980 KB Output is correct
17 Correct 6 ms 11980 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -

Subtask #3
2.0 / 2.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12748 KB Output is correct
2 Correct 10 ms 12748 KB Output is correct
3 Correct 10 ms 12620 KB Output is correct
4 Correct 10 ms 12700 KB Output is correct
5 Correct 10 ms 12668 KB Output is correct
6 Correct 10 ms 12592 KB Output is correct
7 Correct 10 ms 12744 KB Output is correct
8 Correct 11 ms 12748 KB Output is correct
9 Correct 11 ms 12668 KB Output is correct
10 Correct 10 ms 12620 KB Output is correct
11 Correct 10 ms 12736 KB Output is correct
12 Correct 10 ms 12620 KB Output is correct
13 Correct 11 ms 12620 KB Output is correct
14 Correct 10 ms 12620 KB Output is correct

Subtask #4
0.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct
16 Correct 9 ms 11980 KB Output is correct
17 Correct 6 ms 11980 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -

Subtask #5
0.0 / 2.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct
16 Correct 9 ms 11980 KB Output is correct
17 Correct 6 ms 11980 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -

Subtask #6
0.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct
16 Correct 9 ms 11980 KB Output is correct
17 Correct 6 ms 11980 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -

Subtask #7
0.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct
16 Correct 9 ms 11980 KB Output is correct
17 Correct 6 ms 11980 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -

Subtask #8
0.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11984 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 7 ms 11980 KB Output is correct
5 Correct 7 ms 11980 KB Output is correct
6 Correct 7 ms 12024 KB Output is correct
7 Correct 7 ms 11980 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12012 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 8 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 6 ms 11980 KB Output is correct
15 Correct 7 ms 11980 KB Output is correct
16 Correct 9 ms 11980 KB Output is correct
17 Correct 6 ms 11980 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -