#include<iostream>
#include<cstring>
#include<cstdio>
#include<queue>
using namespace std;
const int N=110,M=10010;
int to[M],val[M],nxt[M];
int head[N],dis[N];
bool vis[N];
int n,m,cnt;
void add(int u,int v,int d){
    cnt++;
    val[cnt]=d;
    to[cnt]=v;
    nxt[cnt]=head[u];
    head[u]=cnt;
}
struct node{
    int dis;
    int pos;
    bool operator <(const node &x )const{
        return x.dis<dis;
    }
};
void dijkstra(int s){
    memset(dis,1e9,sizeof(dis));
    memset(vis,0,sizeof(vis));
    dis[s]=0;
    priority_queue<node>q;
    q.push((node){0,s});
    while(!q.empty()){
        node tmp=q.top();
        q.pop();
        int x=tmp.pos,d=tmp.dis;
        if(vis[x])continue;
        vis[x]=1;
        for(int i=head[x];i;i=nxt[i]){
            int y=to[i];
            if(dis[y]>dis[x]+val[i]){ 
                dis[y]=dis[x]+val[i];
                if(!vis[y]){
                    q.push((node){dis[y],y});
                }
            }
        }
    }
}
int main(){
    scanf("%d%d",&n,&m);
    for(int i=0;i<m;++i){
        int u,v,w;int tmp;int s,t;
        scanf("%d",&tmp);
        if(tmp){
            scanf("%d%d%d",&u,&v,&w);
            add(u,v,w);add(v,u,w);
        }
        else{
            scanf("%d%d",&s,&t);
            dijkstra(s);
            if(dis[t]!=1e9)printf("%d\n",dis[t]);
            else printf("-1\n");
        }
    }
    return 0;
}