#include<iostream>

#include<cstring>

#include<cstdio>

using namespace std;

const int N=+;

int p[N];

int w[N];

int find(int x)

{

    if(p[x]==x)

        return x;

    int root=find(p[x]);

    w[x]+=w[p[x]];

    p[x]=root;

    return p[x];

}

int n,m;

int main()

{

    while(~scanf("%d%d",&n,&m))

    {

        for(int i=;i<=n;i++)

            p[i]=i,w[i]=;

        int ans=;

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

        {

            int a,b,c;

            scanf("%d%d%d",&a,&b,&c);

            int pa=find(a);

            int pb=find(b);

            if(pa==pb)

            {

                if(w[a]+c!=w[b])

                    ans++;

            }

            else

            {

                p[pb]=pa;

                w[pb]=w[a]-w[b]+c;

            }

        }

        printf("%d\n",ans);

    }

    return ;

}