题目：裸体最短路，但是要的是n到1的最短路（没区别）
板子题注意先输入T后输入N
#include <iostream> #include <cmath> #include <cstdio> #include <cstring> #include <string> #include <map> #include <iomanip> #include <algorithm> #include <queue> #include <stack> #include <set> #include <vector> //const int maxn = 1e5+5; #define ll long long ll gcd(ll a,ll b){return b?gcd(b,a%b):a;} ll lcm(ll a,ll b){return a/gcd(a,b)*b;} #define MAX INT_MAX #define FOR(i,a,b) for( int i = a;i <= b;++i) #define bug cout<<"--------------"<<endl using namespace std; const int N=100010,M=1000010; int head[N],ver[N],edge[M],next[M],d[N]; int vis[N]; int n,m,tot; priority_queue<pair < int,int> >que; void add(int x,int y,int z) { ver[++tot]=y,edge[tot]=z; next[tot]=head[x],head[x]=tot; } void dijkstra() { memset(d,9999999,sizeof(d)); memset(vis,0,sizeof(vis)); d[n]=0; que.push(make_pair(0,n)); while(que.size()) { int x=que.top().second; que.pop(); if(vis[x]==1) continue; vis[x]=1; for(int i=head[x];i;i=next[i]) { int y=ver[i]; int z=edge[i]; if(d[y]>d[x]+z) { d[y]=d[x]+z; que.push(make_pair(-d[y],y)); } } } } int main() { // freopen("C:\\Users\\方瑞\\Desktop\\input.txt","r",stdin); // freopen("C:\\Users\\方瑞\\Desktop\\output.txt","w",stdout); cin>>m>>n; FOR(i,1,m) { int a,b,c; cin>>a>>b>>c; add(a,b,c); add(b,a,c); } dijkstra(); cout<<d[1]<<endl; // FOR(i,1,n) // { // cout<<d[i]<<endl; // } }