#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))
#define pb(a) push_back(a)
#pragma GCC optimize("O3")
using namespace std;
using namespace __gnu_pbds;
auto random_address = [] { char *p = new char; delete p; return uint64_t(p); };
const uint64_t SEED = chrono::steady_clock::now().time_since_epoch().count() * (random_address() | 1);
mt19937_64 rng(SEED);
typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
ll n,m,flux[1001][1001],cap[1001][1001],ans;
vector<pll> muchii[1001];
deque<pair<pll,ll>> path;
const ll INF=1000000000;
bool use[1001];
void dfs(int nod)
{
    use[nod]=1;
    if(nod==n||use[n])
        return;
    for(auto it:muchii[nod])
    {
        int i=it.first;
        int c=it.second;
        if(use[i])
            continue;
        if(flux[nod][i]<cap[nod][i])
        {
            dfs(i);
            if(use[n])
            {
                path.push_back({{nod,i},c});
                break;
            }
        }
    }
}
int main()
{
    ios_base::sync_with_stdio(false);
    fin.tie(0);
    fout.tie(0);
    fin>>n>>m;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
            cap[i][j]=-1;
    for(int i=1;i<=m;i++)
    {
        int a,b,c;
        fin>>a>>b>>c;
        muchii[a].pb(make_pair(b,c));
        cap[a][b]=c;
    }
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
            if(cap[i][j]!=-1)
                if(cap[j][i]==-1)
                {
                    cap[j][i]=0;
                    muchii[j].pb(make_pair(i,0));
                }
    while(true)
    {
        path.clear();
        memset(use,0,sizeof(use));
        dfs(1);
        if(!use[n])
            break;
        ll val=INF;
        for(auto i:path)
        {
            ll nod1=i.first.first;
            ll nod2=i.first.second;
            ll dif=cap[nod1][nod2]-flux[nod1][nod2];
            val=min(val,dif);
        }
        if(val==INF||val<=0)
            break;
        ans+=val;
        for(auto i:path)
        {
            ll nod1=i.first.first;
            ll nod2=i.first.second;
            flux[nod1][nod2]+=val;
            flux[nod2][nod1]-=val;
        }
    }
    fout<<ans;
    return 0;
}