Submission #525253

# Submission time Handle Problem Language Result Execution time Memory
525253 2022-02-11T07:55:26 Z qwerasdfzxcl Mountains and Valleys (CCO20_day1problem3) C++14
3 / 25
13 ms 12804 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, cyc;
bool dfs0(int s, int e, int pa = -1){
    cyc.push_back(s);
    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;
int calc(int s, int n){
    fill(dist, dist+n, 0);
    dfs(s);
    if (*max_element(dist, dist+n)==0) return 0;

    dfs(max_element(dist, dist+n)-dist);

    return *max_element(dist, dist+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);
    }

    ans = min(ans, cur*2 - calc(0, n));

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

    for (auto &e:E){
        P.clear();
        cyc.clear();
        assert(dfs0(e.v, e.w));

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

        for (auto &x:P){
            on[x] = 0, cur -= W[x];
            ans = min(ans, cur*2 - calc(0, n));
            on[x] = 1, cur += W[x];
        }

        ///cycle
        /*on[e.i] = 0;
        vector<int> deep;

        int len = W[e.i] + P.size();

        for (auto &x:P) on[x] = 0;
        for (auto &x:cyc){
            fill(dist, dist+n, 0);
            dfs(x);
            deep.push_back(*max_element(dist, dist+n));
            ans = min(ans, cur*2-len-calc(x, n));
            //printf("%d: %d\n", x, calc(x, n));
            //for (int i=1;i<=9;i++) printf("%d", on[i]);
            //printf("\n");
        }


        for (int i=0;i<(int)cyc.size();i++){
            int clen = 0;
            for (int j=i+1;j<(int)cyc.size();j++){
                clen++;
                ans = min(ans, cur*2 - (max(clen, len-clen) + deep[i] + deep[j]));
            }
        }*/

        ///

        for (auto &x:P) on[x] = 1;

        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);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
# 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 7 ms 11980 KB Output is correct
18 Incorrect 7 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 13 ms 12804 KB Output is correct
2 Correct 11 ms 12748 KB Output is correct
3 Correct 11 ms 12620 KB Output is correct
4 Correct 10 ms 12664 KB Output is correct
5 Correct 10 ms 12620 KB Output is correct
6 Correct 11 ms 12540 KB Output is correct
7 Correct 10 ms 12736 KB Output is correct
8 Correct 10 ms 12748 KB Output is correct
9 Correct 12 ms 12748 KB Output is correct
10 Correct 11 ms 12640 KB Output is correct
11 Correct 11 ms 12620 KB Output is correct
12 Correct 10 ms 12692 KB Output is correct
13 Correct 11 ms 12620 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 7 ms 11980 KB Output is correct
18 Incorrect 7 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 7 ms 11980 KB Output is correct
18 Incorrect 7 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 7 ms 11980 KB Output is correct
18 Incorrect 7 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 7 ms 11980 KB Output is correct
18 Incorrect 7 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 6 ms 11996 KB Output is correct
4 Correct 6 ms 11980 KB Output is correct
5 Correct 6 ms 12012 KB Output is correct
6 Correct 6 ms 11980 KB Output is correct
7 Correct 6 ms 12048 KB Output is correct
8 Correct 7 ms 12052 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 7 ms 11980 KB Output is correct
11 Correct 6 ms 11980 KB Output is correct
12 Correct 6 ms 12036 KB Output is correct
13 Correct 6 ms 12056 KB Output is correct
14 Correct 6 ms 12052 KB Output is correct
15 Correct 6 ms 11984 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 7 ms 11980 KB Output is correct
18 Incorrect 7 ms 11980 KB Output isn't correct
19 Halted 0 ms 0 KB -