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73 lines
1.5 KiB
C++
73 lines
1.5 KiB
C++
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#include <bits/stdc++.h>
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using namespace std;
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int n, m, x, a, b, head[300005], vis[300005], used[300005], dis[300005], num;
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queue<int> q;
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struct {
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int next, to, val;
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} g[1000005];
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void add(int u, int v, int w) {
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g[++num].next = head[u];
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g[num].to = v;
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g[num].val = w;
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head[u] = num;
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}
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int main() {
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cin >> n >> m;
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for (int i = 1; i <= m; i++) {
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cin >> x >> a >> b;
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if (x == 1) {
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add(a, b, 0);
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add(b, a, 0);
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} else if (x == 2) {
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add(a, b, 1);
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} else if (x == 3) {
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add(b, a, 0);
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} else if (x == 4) {
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add(b, a, 1);
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} else if (x == 5) {
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add(a, b, 0);
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}
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if (x % 2 == 0 && a == b) {
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cout << -1 << endl;
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exit(0);
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}
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}
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for (int i = 1; i <= n; i++) {
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vis[i] = 1;
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dis[i] = 1;
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used[i] = 1;
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q.push(i);
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}
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while (!q.empty()) {
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int z = q.front();
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q.pop();
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if (used[z] >= n - 1) {
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cout << -1 << endl;
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exit(0);
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}
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used[z]++;
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for (int i = head[z]; i; i = g[i].next) {
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int t = g[i].to;
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if (dis[t] < dis[z] + g[i].val) {
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dis[t] = dis[z] + g[i].val;
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if (!vis[t]) {
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q.push(t);
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vis[t] = 1;
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}
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}
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}
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vis[z] = 0;
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}
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long long ans = 0;
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for (int i = 1; i <= n; i++) {
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ans += dis[i];
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}
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cout << ans << endl;
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return 0;
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}
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