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const long long INF = 100000000000; | |
vector<char> used (1000010); | |
vector< vector <int>> gtemp(1000010); | |
int main(){ | |
//20C Usual Dijkstra | |
int n,m,a,b,ok=0; | |
cin >> n >> m; | |
++n; | |
vector < vector <pair<int, int>> > g(n); | |
for (int i = 0; i < m; i++) | |
{ | |
int a, b, w; | |
cin >> a >> b >> w; | |
ok = 0; | |
if (g[a].size() > 0){ | |
for (int j = 0; j<g[a].size(); j++) | |
if (g[a][j].first == b) | |
{ | |
g[a][j].second = min(g[a][j].second,w); | |
ok = 1; | |
} | |
if (ok == 0) | |
g[a].push_back(make_pair(b,w)); | |
} | |
else{ | |
g[a].push_back(make_pair(b, w)); | |
} | |
ok = 0; | |
if (g[b].size() > 0){ | |
for (int j = 0; j<g[b].size(); j++) | |
if (g[b][j].first == a) | |
{ | |
g[b][j].second = min(g[b][j].second, w); | |
ok = 1; | |
} | |
if (ok == 0) | |
g[b].push_back(make_pair(a,w)); | |
} | |
else{ | |
g[b].push_back(make_pair(a, w)); | |
} | |
/* g[a].push_back(make_pair(b, w)); | |
g[b].push_back(make_pair(a, w));*/ | |
} | |
cin >> a >> b; | |
int s = a;//1 | |
vector<long long> d(n, INF), p(n); | |
d[s] = 0; | |
vector<char> u(n); | |
for (int i = 0; i < n; i++) | |
{ | |
int v = -1; | |
for (int j = 0; j < n; ++j)//b | |
if (!u[j] && (v == -1 || d[j] < d[v])) | |
v = j; | |
if (d[v] == INF) | |
break; | |
u[v] = true; | |
for (size_t j = 0; j < g[v].size(); ++j) | |
{ | |
int to = g[v][j].first, | |
len = g[v][j].second; | |
if (d[v] + len < d[to]){ | |
d[to] = d[v] + len; | |
p[to] = v; | |
} | |
} | |
} | |
cout << d[b] << endl; | |
return 0; | |
} |
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