#include <bits/stdc++.h>
using namespace std;
#define int long long
vector<vector<pair<int,int>>>g(3e5+5);
vector<long long>dp2(3e5+5,-1);
vector<long long>dp(3e5+5,-1);
signed main()
{
// freopen("5-10.in", "r", stdin);
int n,m;
cin >> n>>m;
// cin >> n >> m;
vector<pair<int,int>>e(m+1);
for(int i = 1;i<=m;i++)
{
int a,b,w;
cin >> a >> b >> w;
//cout << 'o';
g[a].push_back({b,i});
g[b].push_back({a,i});
e[i] = {a,b};
//cout << 'o';
}
//dfs();
dp[1] =0;
queue<int>q;
q.push(1);
while(!q.empty())
{
int v = q.front();
q.pop();
for(auto u : g[v])
{
if(dp[u.first] == -1)
{
q.push(u.first);
dp[u.first] = dp[v] + 1;
}
}
}
dp2[n] =0;
//queue<int>q;
q.push(n);
while(!q.empty())
{
int v = q.front();
q.pop();
for(auto u : g[v])
{
if(dp2[u.first] == -1)
{
q.push(u.first);
dp2[u.first] = dp2[v] + 1;
}
}
}
int mn = 1e9+5;
int num = 0;
int mn2 = 1e9+5;
map<int,int>mp;
int s =1;
for(int i = 1;i<=m;i++)
{
int u = e[i].first;
int v = e[i].second;
if(dp[u] + dp2[v]+1 == dp[n])
{
mp[dp[u]]++;
if(i==m)mp[d[u]]++;
//cout << 'u';
}
if(dp[v] + dp2[u]+1 == dp[n])
{
mp[dp[v]]++;
if(i==m)mp[d[v]]++;
//cout << 'u';
}
/*/if(i==m && (dp[u] + dp2[v]+1 <mn+mn2+1))
{
num++;
s= 0;
}/*/
// cout << dp[i.first] + dp2[i.second]+1 << '\n';
}
for(int i = 1;i<dp[n];i++)
{
if(mp[i]==1)num=1;
}
cout << dp[n] + ((num ==1));
}
Compilation message
Aesthetic.cpp: In function 'int main()':
Aesthetic.cpp:73:19: error: 'd' was not declared in this scope
73 | if(i==m)mp[d[u]]++;
| ^
Aesthetic.cpp:79:19: error: 'd' was not declared in this scope
79 | if(i==m)mp[d[v]]++;
| ^
Aesthetic.cpp:60:7: warning: unused variable 'mn' [-Wunused-variable]
60 | int mn = 1e9+5;
| ^~
Aesthetic.cpp:62:7: warning: unused variable 'mn2' [-Wunused-variable]
62 | int mn2 = 1e9+5;
| ^~~
Aesthetic.cpp:64:7: warning: unused variable 's' [-Wunused-variable]
64 | int s =1;
| ^
