Submission #753707

#	Time	Username	Problem	Language	Result	Execution time	Memory
753707		keta_tsimakuridze	Training (IOI07_training)	C++14	30 / 100	1075 ms	11872 KiB

training

#include<bits/stdc++.h>
#define f first
#define s second
#define int long long
#define pii pair<int,int>
using namespace std;
const int N = 2e5 + 5, mod = 1e9 + 7; // !
int t, in[N], out[N], timer, P[N][20], dp[N], fw[N], h[N];
vector<int> V[N];
vector<pair<pair<int,int>, int> > x[N];
void dfs0(int u, int p) {
    in[u] = ++timer;
    h[u] = h[p] + 1;
    P[u][0] = p;
    for(int i = 1; i <= 18; i++) P[u][i] = P[P[u][i - 1]][i - 1];
    for(int i = 0; i < V[u].size(); i++) {
        int v = V[u][i];
        if(v != p) dfs0(v, u);
    }
    out[u] = timer;
}
bool check(int u, int v) {
    return (in[u] <= in[v] && out[v] <= out[u]);
}
int lca(int u, int v) {
    if(check(u, v)) return u;
    if(check(v, u)) return v;

    for(int i = 18; i >= 0; i--) {
        if(P[u][i] && !check(P[u][i], v)) u = P[u][i];
    }
    return P[u][0];
}
int n;
void upd(int id, int x) {
    for(id; id <= n; id += id & (-id)) fw[id] += x;
}
int get(int id) {
    int ans = 0;
    for(id; id >= 1; id -= id & (-id)) ans += fw[id];
    return ans;
}
int up(int u, int x) {
    for(int i = 0; i <= 18; i++) {
        if((1 << i) & x) u = P[u][i];
    }
    return u;
}
void dfs(int u, int p) {
    int tot = 0;
    for(int i = 0; i < V[u].size(); i++) {
        if(V[u][i] != p) dfs(V[u][i], u), tot += dp[V[u][i]];
    }
    vector<vector<int>> bad;
    bad.resize((int)x[u].size(), vector<int> ((int)x[u].size()));
    for(int i = 0; i < (int)x[u].size(); i++) {
        for(int j = 0; j < (int)x[u].size(); j++) {
            if(i == j) continue;
            bad[i][j] = (lca(x[u][i].f.f, x[u][j].f.f) != u || lca(x[u][i].f.f, x[u][j].f.s) != u ||
              lca(x[u][i].f.s, x[u][j].f.f) != u || lca(x[u][i].f.s, x[u][j].f.s) != u );
        }
    }
    dp[u] = tot;
    for(int mask = 0; mask < (1 << (int)x[u].size()); mask++) {
        vector<int> v;
        int F = 0, cur = 0;
        for(int i = 0; i < (int)x[u].size(); i++) {
            if((1 << i) & mask) {
                if(x[u][i].f.f != u)
                v.push_back(x[u][i].f.f);
                if(x[u][i].f.s != u)
                v.push_back(x[u][i].f.s);
                for(int j = 0; j < (int)x[u].size(); j++) {
                    if((1 << j) & mask) F |= bad[i][j];
                }
                cur += x[u][i].s;
            }
        }
        if(F) continue;
        cur += tot;

        for(int i = 0; i < v.size(); i++) {
            cur -= dp[up(v[i], h[v[i]] - h[u] - 1)];
            cur += get(in[v[i]]);
        }
        dp[u] = max(dp[u], cur);
    }
    for(int i = 0; i < V[u].size(); i++) {
        if(V[u][i] == p) continue;
        upd(in[V[u][i]], tot - dp[V[u][i]]);
        upd(out[V[u][i]] + 1, -(tot - dp[V[u][i]]));
    }
    upd(in[u], dp[u]);
    upd(in[u] + 1, -dp[u]);
}
main(){
    int m;
    cin >> n >> m;
    vector<pair<pair<int,int>, int> > e;
    while(m--) {
        int u, v, c;
        cin >> u >> v >> c;
        if(!c) V[u]. push_back(v), V[v].push_back(u);
        else {
            e.push_back({{u, v}, c});
        }
    }
    int root = 1;
    for(int i = 1; i <= n; i++) if(V[i].size() == 1) root = i;
    dfs0(root, 0);
    int ans = 0, all = 0;
    for(int i = 0; i < e.size(); i++) {
        int u = e[i].f.f, v = e[i].f.s, c = e[i].s;
        if((h[u] + h[v] - 2 * h[lca(u, v)]) % 2) {
            ans += c; continue;
        }
        all += c;
        x[lca(u, v)].push_back({{u, v}, c});
    }
    dfs(root, 0);
    cout << all - dp[root] + ans;
}

Compilation message (stderr)

training.cpp: In function 'void dfs0(long long int, long long int)':
training.cpp:16:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
training.cpp: In function 'void upd(long long int, long long int)':
training.cpp:36:9: warning: statement has no effect [-Wunused-value]
   36 |     for(id; id <= n; id += id & (-id)) fw[id] += x;
      |         ^~
training.cpp: In function 'long long int get(long long int)':
training.cpp:40:9: warning: statement has no effect [-Wunused-value]
   40 |     for(id; id >= 1; id -= id & (-id)) ans += fw[id];
      |         ^~
training.cpp: In function 'void dfs(long long int, long long int)':
training.cpp:51:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
training.cpp:82:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   82 |         for(int i = 0; i < v.size(); i++) {
      |                        ~~^~~~~~~~~~
training.cpp:88:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |     for(int i = 0; i < V[u].size(); i++) {
      |                    ~~^~~~~~~~~~~~~
training.cpp: At global scope:
training.cpp:96:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   96 | main(){
      | ^~~~
training.cpp: In function 'int main()':
training.cpp:112:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<std::pair<long long int, long long int>, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  112 |     for(int i = 0; i < e.size(); i++) {
      |                    ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 0 / 7
• Subtask 5: 0 / 9
• Subtask 6: 0 / 9
• Subtask 7: 0 / 9
• Subtask 8: 0 / 9
• Subtask 9: 0 / 9
• Subtask 10: 0 / 9
• Subtask 11: 0 / 9