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#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a); i <= (b); ++i)
#define ROF(i, a, b) for (int i = (a); i >= (b); --i)
#define all(x) x.begin(),x.end()
#define CLR(i,a) memset(i,a,sizeof(i))
#define fi first
#define se second
#define pb push_back
#define SZ(a) ((int) a.size())
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pll;
typedef array<ll,2> arr;
typedef double DB;
typedef pair<DB,DB> pdd;
typedef pair<ll,bool> plb;
constexpr ll MAXN=static_cast<ll>(1e6)+10,INF=static_cast<ll>(5e18)+3;
ll N,M,X,T,A[MAXN];
vector<ll> g[MAXN];
ll dist[MAXN];
struct cmp{
bool operator()(const arr &a,const arr &b)const{
return a[1]>b[1];
}
};
inline void solve(){
cin>>N>>M>>X;
FOR(i,1,2*N){
dist[i]=INF;
}
FOR(i,1,M){
ll u,v;
cin>>u>>v;
g[u].pb(v);
g[v+N].pb(u+N);
}
priority_queue<arr,vector<arr>,cmp> pq;
pq.push({1,0});
while(!pq.empty()){
ll node=pq.top()[0],dis=pq.top()[1];
pq.pop();
if(dist[node]==INF){
dist[node]=dis;
FOR(i,0,SZ(g[node])-1 ){
ll toNode=g[node][i];
pq.push({toNode,dis+1});
}
if(node>N){
pq.push({node-N,dis+X});
}else{
pq.push({node+N,dis+X});
}
}
}
cout<<min(dist[N],dist[2*N])<<"\n";
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
solve();
return 0;
}
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