Submission #1057090

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Source Code Expand

#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <deque>
#include <iomanip>
#include <iostream>
#include <limits>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <vector>

#define FOR(i,k,n) for (int (i)=(k); (i)<(n); ++(i))
#define rep(i,n) FOR(i,0,n)
#define pb push_back
#define all(v) begin(v), end(v)
#define debug(x) cerr<< #x <<": "<<x<<endl
#define debug2(x,y) cerr<< #x <<": "<< x <<", "<< #y <<": "<< y <<endl

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vector<int> > vvi;
typedef vector<ll> vll;
typedef vector<vector<ll> > vvll;
template<class T> using vv=vector<vector< T > >;

#define INF 2e9
int n, m;

vector<vector<int> > cost; // 隣接行列
vector<int> d; // 仮のコストの最小値、最終結果
deque<bool> used;
vector<set<pii> > route;

void dijkstra(int s) {
  d.assign(n, INF);
  used.assign(n, false);
  d[s] = 0;

  while (true) {
    int v = -1;
    rep (u, n) {
      if (!used[u] && (v == -1 || d[u] < d[v])) {
        v = u;
      }
    }
    if (v == -1) {
      break;
    }
    used[v] = true;
    rep (u, n) {
      if (d[u] > d[v] + cost[v][u]) {
        route[u] = route[v];
        route[u].insert({min(v, u), max(v, u)});
        d[u] = d[v] + cost[v][u];
      } else if (d[u] == d[v] + cost[v][u]) {
        route[u].insert({min(v, u), max(v, u)});
      }
    }
  }
}

int main() {
  scanf("%d %d", &n, &m);
  cost.assign(n, vi(n, INF));
  rep (i, n) {
    cost[i][i] = 0;
  }
  set<pii> all_edge;
  rep (i, m) {
    int a, b, c;
    scanf("%d %d %d", &a, &b, &c);
    a -= 1; b -= 1;
    cost[a][b] = cost[b][a] = c;
    all_edge.insert(make_pair(min(a, b), max(a, b)));
  }
  route.resize(n);
  rep (i, n) {
    rep (j, n) {
      route[j].clear();
    }
    dijkstra(i);
    rep (j, n) {
      for (pii p : route[j]) {
        all_edge.erase(p);
      }
    }
  }
  printf("%d\n", (int)all_edge.size());

  return 0;
}

Submission Info

Judge Result