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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#118117 | #6560. Broken Minimum Spanning Tree | cada_dia_mas_insanos | WA | 1ms | 3408kb | C++17 | 2.5kb | 2023-07-03 08:42:38 | 2023-07-03 08:42:41 |
Judging History
answer
// Too many mind, no mind.
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <queue>
#include <ctime>
#include <cassert>
#include <complex>
#include <string>
#include <cstring>
#include <chrono>
#include <random>
#include <bitset>
#include <array>
#include <iomanip>
using namespace std;
#define mp make_pair
#define fi first
#define se second
#define pb push_back
#define ALL(x) (x).begin(), (x).end()
#define RALL(x) (x).rbegin(), (x).rend()
#define COMP(x) sort(ALL(x)); x.resize(unique(ALL(x)) - (x).begin())
#define forn(i, n) for (int i = 0; i < (int)(n); ++i)
#define fore(i, a, b) for (int i = (int)(a); i <= (int)(b); ++i)
#define ford(i, n) for (int i = (int)(n) - 1; i >= 0; --i)
using pii = pair <int, int>;
using vi = vector <int>;
using vpi = vector <pii>;
using ll = long long;
using pll = pair<ll, ll>;
using vl = vector<ll>;
using ld = long double;
using vld = vector<ld>;
using pp = pair<pll, pll>;
struct DSU {
int n;
vi f, s;
DSU (int n): n(n) {
f.resize(n); iota(ALL(f), 0);
s.assign(n, 1);
}
int find(int a) { return f[a] = f[a] == a ? a : find(f[a]); }
void merge(int a, int b) {
a = find(a), b = find(b);
if (a == b) return;
if (s[a] < s[b]) swap(a, b);
s[a] += s[b];
f[b] = a;
}
};
int main() {
ios_base::sync_with_stdio(0), cin.tie(0);
//freopen("input.txt", "r", stdin);
//freopen("output.txt", "w", stdout);
int n, m; cin >> n >> m;
vector <pp> edges(m);
forn(i, m) {
int u, v, w; cin >> u >> v >> w;
u--, v--;
edges[i] = mp(mp(w, i), mp(u, v));
}
sort(ALL(edges));
DSU mst(n);
ll w = 0;
forn(i, m) {
int u = edges[i].se.fi, v = edges[i].se.se;
int c = edges[i].fi.fi;
if (mst.find(u) == mst.find(v)) continue;
w += c;
mst.merge(u, v);
}
vector <bool> in(m, 0);
forn(i, m) {
DSU dsu(n);
int u = edges[i].se.fi, v = edges[i].se.se;
int c = edges[i].fi.fi;
int k = edges[i].fi.se;
dsu.merge(u, v);
ll cur = c;
forn(j, m) if (i != j) {
u = edges[j].se.fi, v = edges[j].se.se;
c = edges[j].fi.fi;
if (dsu.find(u) == dsu.find(v)) continue;
cur += c;
dsu.merge(u, v);
}
in[k] = cur == w;
}
vpi ans;
for(int i = 0, j = n-1; i<n-1; i++) {
if (in[i]) continue;
while (j < m && !in[j]) j++;
ans.pb(mp(i, j));
j++;
}
cout << ans.size() << endl;
for(auto& it : ans) cout << it.fi+1 << ' ' << it.se+1 << endl;
return 0;
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3400kb
input:
4 4 1 2 10 2 3 3 3 4 1 1 4 4
output:
1 1 4
result:
ok correct!
Test #2:
score: -100
Wrong Answer
time: 1ms
memory: 3408kb
input:
6 8 1 2 10 2 3 10 3 4 10 4 5 10 5 6 10 6 1 10 1 3 1 4 6 1
output:
0
result:
FAIL participant's MST is better than jury!