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#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
const int INF = 1e9; // INF = 1B, not 2^31-1 to avoid overflow
int main() {
/*
// Graph in Figure 4.18, has negative weight, but no negative cycle
5 5 0
0 1 1
0 2 10
1 3 2
2 3 -10
3 4 3
// Graph in Figure 4.19, negative cycle exists, SPFA will be trapped in an infinite loop/produces WA (stop only when overflow happens)
6 6 0
0 1 99
0 5 -99
1 2 15
2 3 0
3 1 -42
3 4 2
*/
freopen("bellman_ford_in.txt", "r", stdin);
int V, E, s; scanf("%d %d %d", &V, &E, &s);
vector<vii> AL(V, vii());
while (E--) {
int u, v, w; scanf("%d %d %d", &u, &v, &w);
AL[u].emplace_back(v, w);
}
// SPFA from source S
vi dist(V, INF); dist[s] = 0; // INF = 1e9 here
queue<int> q; q.push(s); // like BFS queue
vi in_queue(V, 0); in_queue[s] = 1; // unique to SPFA
while (!q.empty()) {
int u = q.front(); q.pop(); in_queue[u] = 0; // pop from queue
for (auto &[v, w] : AL[u]) { // C++17 style
if (dist[u]+w >= dist[v]) continue; // not improving, skip
dist[v] = dist[u]+w; // relax operation
if (!in_queue[v]) { // add to the queue
q.push(v); // only if v is not
in_queue[v] = 1; // already in the queue
}
}
}
for (int u = 0; u < V; ++u)
printf("SSSP(%d, %d) = %d\n", s, u, dist[u]);
return 0;
}