萌新求捉虫
本地环境为WSL Ubuntu 22.04
编译参数: -g -O2 -Wall -Wextra
code:

#include<bits/stdc++.h>
using namespace std;
template <typename Tp>
inline void read(Tp &x){
    x=0;
    int f(1);
    char ch=getchar();
    while(ch<'0'||ch>'9'){
        if(ch=='-')f=-1;
        ch=getchar();
    }while(ch>='0'&&ch<='9'){
        x=(x<<1)+(x<<3)+(ch^48);
        ch=getchar();
    }
    x*=f;
    return;
}
void print(long long x){
    if(x<0)putchar('-'),x=-x;
    if(x>9)print(x/10);
    putchar(x%10+48);
    return;
}
const int n=26*2;
char u,v,anss;
int p,w,ans(0x3f3f3f3f);
#define MAXN 500005
#define INF 2147483647;
bitset<MAXN>vis;
int head[MAXN],dis[MAXN],cnt[MAXN],ecnt(0);
struct edge{
    int to,next,w;
}e[MAXN];
inline int getnum(char ch){
    return ch-'A';
}
inline void addedge(int u,int v,int w){
    e[++ecnt]={v,head[u],w},head[u]=ecnt;
    e[++ecnt]={u,head[v],w},head[v]=ecnt;
}
inline void init(){
    for(int i='A';i<='z';++i){
        head[i]=cnt[i]=vis[i]=0;
    }
}
inline void spfa(int s){
    for(int i='A';i<='z';++i)dis[i]=INF;
    queue<int>q;
    q.push(s),dis[s]=0,vis[s]=1;
    while(!q.empty()){
        int u(q.front());
        q.pop();
        vis[u]=0;
        for(int i=head[u];i;i=e[i].next){
            int v(e[i].to);
            if(dis[v]>dis[u]+e[i].w){
                dis[v]=dis[u]+e[i].w;
                if(!vis[v]){
                    vis[v]=1;
                    q.push(v);
                }
            }
        }
    }
}

int main(){
    #ifndef ONLINE_JUDGE
        freopen("test.in","r",stdin);
    #endif
    read(p);
    init();
    for(int i=1;i<=p;++i){
        scanf("%c %c",&u,&v),read(w);
        addedge((int)u,(int)v,w);
    }
    spfa((int)'Z');
    for(int i='A';i<'Z';++i){
        if(ans>dis[i]){
            anss=char(i);
            ans=dis[i];
        }
    }
    putchar_unlocked(anss),putchar_unlocked(' '),print(ans);
    //cout<<anss<<" ";print(ans);
    return 0;
}

样例本地输出:B 11
在线IDE输出:(ASCII 0) 1061109567