#include<cstdio>

#include<cstring>

#include<cmath>

#include<iostream>

#include<algorithm>

#include<set>

#include<map>

#include<stack>

#include<vector>

#include<queue>

#include<string>

#include<sstream>

#define eps 1e-9

#define ALL(x) x.begin(),x.end()

#define INS(x) inserter(x,x.begin())

#define FOR(i,j,k) for(int i=j;i<=k;i++)

#define MAXN 1005

#define MAXM 40005

#define INF 0x3fffffff

using namespace std;

typedef long long LL;

int i,j,k,n,m,x,y,ans,big,cas,num,w,t,u,v,S,T;

bool flag;

int head[MAXN],vis[MAXN],dis[MAXN],pos[MAXN],Edge,size;

char s[305][305];

struct edgenode

{

    int to,next,w,cost;

} edge[MAXM];

void add_edge(int x,int y,int w,int cost)

{

    edge[Edge].to=y;

    edge[Edge].w=w;

    edge[Edge].cost=cost;

    edge[Edge].next=head[x];

    head[x]=Edge;

    Edge++;

    edge[Edge].to=x;

    edge[Edge].w=0;

    edge[Edge].cost=-cost;

    edge[Edge].next=head[y];

    head[y]=Edge;

    Edge++;

}

bool SPFA(int s, int t)

{

    int u,v,i;

    queue <int> q;

    memset(vis,0,sizeof(vis));

    for(i=0;i<size;i++) dis[i]=INF;

     dis[s]=0;

     vis[s]=1;

    q.push(s);

    while(!q.empty())

    {

        u=q.front(); q.pop(); vis[u]=0;

        for (i=head[u];i!=-1;i=edge[i].next)

          {

               v=edge[i].to;

               if(edge[i].w>0&&dis[u]+edge[i].cost<dis[v])

               {

                dis[v]=dis[u]+edge[i].cost;

                pos[v]=i;

                if(!vis[v])

                {

                     vis[v]=1;

                     q.push(v);

                }

               }

          }

    }

    return dis[t]!=INF;

}

int MinCostFlow(int s,int t)

{

    int i,cost=0,flow=0;

    while(SPFA(s,t))

    {

        int d=INF;

        for (i=t;i!=s;i=edge[pos[i]^1].to)

        {

            d=min(d,edge[pos[i]].w);

        }

        for(i=t;i!=s;i=edge[pos[i]^1].to)

        {

            edge[pos[i]].w-=d;

            edge[pos[i]^1].w+=d;

        }

        flow+=d;

        cost+=dis[t]*d;

    }

    return cost; // flow是最大流值

}

int main()

{

	memset(head,-1,sizeof(head));Edge=0;

	scanf("%d%d",&n,&m);

	for (i=1;i<=m;i++)

	{

		scanf("%d%d%d",&x,&y,&t);

		add_edge(x,y,1,t);

		add_edge(y,x,1,t);

	}

	S=0;T=n+1;

	size=n+2;

	add_edge(S,1,2,0);

	add_edge(n,T,2,0);

	printf("%d\n",MinCostFlow(S,T));

	return 0;

}