oj.uz

Submission #525666

# Submission time Handle Problem Language Result Execution time Memory
525666 2022-02-12T12:44:35 Z qwerasdfzxcl Mountains and Valleys (CCO20_day1problem3) C++14
2 / 25
 3024 ms 13164 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();
        cyc.pop_back();
    }
    return 0;
}
 
int MX, IDX;
void dfs(int s, int pa = -1, int w = 0){
    if (pa==-1) dist[s] = 0;
    else dist[s] = dist[pa] + w;
 
    if (dist[s]>MX){
        MX = dist[s], IDX = s;
    }
    for (auto &v:adj[s]) if (v.v!=pa && on[v.i]) dfs(v.v, s, v.w);
}
 
int cur = 0, ans = 1e9;
int calc(int s, int n){
    MX = 0, IDX = s;
    dfs(s);
    if (MX==0) return 0;
 
    MX = 0;
    dfs(IDX);
 
    return MX;
}
 
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);
    }
 
    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));
 
        cur += W[e.i];
        int len = W[e.i] + P.size();
 
        for (auto &x:P) on[x] = 0;
 
        ///cycle
        for (auto &x:cyc) ans = min(ans, cur*2 - len - calc(x, n));
 
        ///tree
        vector<int> deep, mx(cyc.size(), -1e9);
        for (auto &x:cyc){
            MX = 0, IDX = x;
            dfs(x);
            deep.push_back(MX);
        }
 
        for (int i=(int)cyc.size()-1;i>=0;i--){
            if (i+1<(int)cyc.size()) mx[i] = mx[i+1];
            mx[i] = max(mx[i], deep[i]-i);
        }
 
        for (int i=0;i<(int)cyc.size()-1;i++){
            //ans = min(ans, (cur-1)*2 - (len + deep[i] + i + mx[i+1]));
        }
 
        ///
 
        for (auto &x:P) on[x] = 1;
 
        cur -= W[e.i];
    }
 
    printf("%d\n", ans);
    return 0;
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:52:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   52 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:55:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   55 |         scanf("%d %d %d", &x, &y, &z);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0.0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11980 KB Output is correct
2 Correct 6 ms 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 Halted 0 ms 0 KB -

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 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #3
2.0 / 2.0

# Verdict Execution time Memory Grader output
1 Correct 2938 ms 13052 KB Output is correct
2 Correct 2385 ms 13164 KB Output is correct
3 Correct 2452 ms 12844 KB Output is correct
4 Correct 2671 ms 12928 KB Output is correct
5 Correct 2680 ms 12872 KB Output is correct
6 Correct 2204 ms 12624 KB Output is correct
7 Correct 2069 ms 13024 KB Output is correct
8 Correct 2519 ms 12876 KB Output is correct
9 Correct 2407 ms 12944 KB Output is correct
10 Correct 3024 ms 12836 KB Output is correct
11 Correct 2982 ms 13004 KB Output is correct
12 Correct 2123 ms 12800 KB Output is correct
13 Correct 2974 ms 12880 KB Output is correct
14 Correct 2863 ms 12896 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 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 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 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 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 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 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 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 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 11992 KB Output is correct
3 Correct 7 ms 12004 KB Output is correct
4 Correct 9 ms 12108 KB Output is correct
5 Correct 6 ms 11980 KB Output is correct
6 Correct 8 ms 11980 KB Output is correct
7 Correct 8 ms 11952 KB Output is correct
8 Correct 6 ms 11980 KB Output is correct
9 Correct 7 ms 12056 KB Output is correct
10 Correct 6 ms 11980 KB Output is correct
11 Incorrect 7 ms 11980 KB Output isn't correct
12 Halted 0 ms 0 KB -