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Cod sursa(job #632566)
#include<cstdio>
#include<algorithm>
#include<vector>
#include<queue>
using namespace std;
const int N = 50005;
int n, m, l[N];
char s[30];
vector<pair<int, int> > v[N];
priority_queue<pair<int, int> > heap;
void parsare(char ss[], int &x, int &y, int &c) {
x = 0;
y = 0;
c = 0;
int i = 0;
while (ss[i] != ' ') {
x = x * 10 + (ss[i] - '0');
++i;
}
++i;
while (ss[i] != ' ') {
y = y * 10 + (ss[i] - '0');
++i;
}
++i;
while (ss[i] && ss[i] != ' ' && ss[i] != '\n') {
c = c * 10 + (ss[i] - '0');
++i;
}
}
void init(char ss[]) {
for (int i = 0; ss[i]; ++i)
ss[i] = 0;
}
void citire() {
freopen("dijkstra.in", "r", stdin);
freopen("dijkstra.out", "w", stdout);
scanf("%d%d\n", &n, &m);
int c, x, y;
for (int i = 1; i <= m; ++i) {
gets(s);
parsare(s, x, y, c);
init(s);
v[x].push_back(make_pair(c, y));
}
}
void rez() {
heap.push(make_pair(0, 1)); // adaug perechea de cost 0 catre nodul 1 in heap
// costul initial este 0
while (!heap.empty()) { // cat timp nu am terminat
pair<int, int> nodc = heap.top(); // retin nodul curent
heap.pop(); // scot din heap
if (!l[nodc.second]) { // daca nu am mai trecut prin nodul curent
l[nodc.second] = nodc.first; // pun costul
// parcurg vecinii
for (vector<pair<int, int> >::iterator it = v[nodc.second].begin(); it != v[nodc.second].end(); ++it)
if (!l[it->second]) // daca nu am mai trecut prin nod
heap.push(make_pair(nodc.first - it->first, it->second));
// pun in heap nodul urmator; costul lui va fi egal cu (-1) * costul curent + costul muchiei
// costul initial este 0.
}
}
// fiindca am inceput de la costul 0 si am mers descendent, toate costurile se trec cu plus
for (int i = 2; i <= n; ++i)
l[i] *= (-1);
}
void afis() {
for (int i = 2; i <= n; ++i)
printf("%d ", l[i]);
}
int main() {
citire();
rez();
afis();
return 0;
}