//蒟蒻 最短路 #include<cstdio>#include<cstring>#include<cstdlib>#include<iostream>#include<algorithm>#include<cmath>#include<queue>using namespace std;int main(){    int n,m,edge[110][110];    scanf("%d%d",&n,&m);        for(int i=1;i<=n;i++)        for(int j=1;j<=n;j++)            edge[i][j] = 999999999;            for(int i=1;i<=m;i++)    {        int x,y,z;        scanf("%d%d%d",&x,&y,&z);        edge[x][y] = z;    }    for(int i=1;i<=n;i++)        edge[i][i] = 0;        for(int k=1;k<=n;k++)    for(int i=1;i<=n;i++)    for(int j=1;j<=n;j++)    {        if(edge[i][j]>edge[i][k]+edge[k][j])            edge[i][j]=edge[i][k]+edge[k][j];    }        int s,t;    scanf("%d%d",&s,&t);    cout<<edge[s][t]<<endl;    return 0;}