Submission #524856

# Submission time Handle Problem Language Result Execution time Memory
524856 2022-02-10T06:58:31 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;
void calc(int n){
    dfs(0);
    dfs(max_element(dist, dist+n)-dist);

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

int main(){
    int n, m;
    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();
        dfs0(e.v, e.w);
        //printf("%d %d: ", e.v, e.w);
        //for (auto &x:P) printf("%d ", x);
        //printf("\n");
        if ((int)P.size()<=W[e.i]) continue;

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

        for (auto &x:P){
            assert(W[x]==1);
            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:41:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:44:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |         scanf("%d %d %d", &x, &y, &z);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
16 Correct 6 ms 12076 KB Output is correct
17 Correct 6 ms 12032 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 10 ms 12748 KB Output is correct
2 Correct 10 ms 12748 KB Output is correct
3 Correct 11 ms 12620 KB Output is correct
4 Correct 10 ms 12632 KB Output is correct
5 Correct 11 ms 12588 KB Output is correct
6 Correct 11 ms 12620 KB Output is correct
7 Correct 11 ms 12748 KB Output is correct
8 Correct 11 ms 12748 KB Output is correct
9 Correct 10 ms 12748 KB Output is correct
10 Correct 10 ms 12620 KB Output is correct
11 Correct 10 ms 12620 KB Output is correct
12 Correct 10 ms 12744 KB Output is correct
13 Correct 12 ms 12672 KB Output is correct
14 Correct 10 ms 12748 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
16 Correct 6 ms 12076 KB Output is correct
17 Correct 6 ms 12032 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
16 Correct 6 ms 12076 KB Output is correct
17 Correct 6 ms 12032 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
16 Correct 6 ms 12076 KB Output is correct
17 Correct 6 ms 12032 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
16 Correct 6 ms 12076 KB Output is correct
17 Correct 6 ms 12032 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 7 ms 11980 KB Output is correct
3 Correct 7 ms 11980 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 6 ms 12008 KB Output is correct
7 Correct 6 ms 11980 KB Output is correct
8 Correct 7 ms 12020 KB Output is correct
9 Correct 6 ms 11980 KB Output is correct
10 Correct 6 ms 12068 KB Output is correct
11 Correct 6 ms 12028 KB Output is correct
12 Correct 7 ms 11980 KB Output is correct
13 Correct 7 ms 11980 KB Output is correct
14 Correct 7 ms 11980 KB Output is correct
15 Correct 6 ms 11980 KB Output is correct
16 Correct 6 ms 12076 KB Output is correct
17 Correct 6 ms 12032 KB Output is correct
18 Incorrect 6 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -