#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
typedef long long ll;
typedef pair<ll,ll> pll;

#define fi first
#define se second
#define pb push_back
#define rank kgjksjsias
const int MAXN = 30000+10;


ll dif[MAXN];

vector<pll> g[MAXN];

set<pll> gr[MAXN];


char used[MAXN];
void dfs(int v){
    used[v]=1;
    for(pll x:g[v]){
        int to = x.se;
        if(!used[to]){
            dfs(to);
        }
    }
}


void merge_set(int a,int b){
    if(gr[a].size()<gr[b].size()){
        swap(gr[a],gr[b]);
    }
    for(pll x:gr[b]){
        ll len = x.fi;
        int to = x.se;
        len = len - dif[b] + dif[a];
        gr[a].insert({len,to});
    }
}
int parent[MAXN];
int rank[MAXN];
int find_parent(int v){
    if(v==parent[v]){
        return v;
    }
    return parent[v] = find_parent(parent[v]);
}

void union_set(int a,int b){
    a = find_parent(a);
    b = find_parent(b);
    if(a!=b){
        if(rank[a]<rank[b])
            swap(a,b);
        else if(rank[a]==rank[b])
            rank[a]++;
        parent[b] = a;
        merge_set(a,b);
    }
}



char us[MAXN];

void solve(){
    int n,m;
    cin >> n >> m;
    for(int i=1;i<=m;++i){
        int a,b,c;
        cin >> a >> b >> c;
        if(a==b)
            continue;
        g[a].pb({c,b});
        gr[b].insert({c,a});
    }

    dfs(1);
    ll ans = 0;
    priority_queue<int> ver;
    for(int i=1;i<=n;++i){
        if(!used[i]){
            cout <<"NO";
            exit(0);
        }

        parent[i] = i;
        if(i>1)
            ver.push(i);
    }
    stack<int> st;
    while(!ver.empty()){
        int v = ver.top(); ver.pop();
        if(find_parent(v)!=v || find_parent(v)==find_parent(1)){
            continue;
        }
        st.push(v);

        while(1){
            us[v] = 1;
            pll x = *gr[v].begin(); gr[v].erase(gr[v].begin());
            ll len = x.fi + dif[v];
            int to = find_parent(x.se);
            if(find_parent(to)==find_parent(v))
                continue;
            ans+=len;
            if(find_parent(to)==find_parent(1)){
                while(!st.empty()){
                    int x = st.top(); st.pop();
                    union_set(x,1);
                }
                break;
            } else if(us[to]==0){
                st.push(to);
                v = to;
            } else {
                while(!st.empty()){
                    int x = st.top(); st.pop();
                    union_set(x,v);
                    if(find_parent(x)==find_parent(to)){
                        break;
                    }
                }
                v = to;
            }

        }
    }

    cout <<"YES\n";
    cout << ans<<endl;

}
int main(){
    #ifdef zxc
        freopen("input.txt","r",stdin);
        freopen("output.txt","w",stdout);
    #endif // zxc
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    solve();;
}