#include <bits/stdc++.h>
using namespace std;
#define ms(s, n) memset(s, n, sizeof(s))
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define FORd(i, a, b) for (int i = (a); i >= (b); --i)
#define FORall(it, a) for (__typeof((a).begin()) it = (a).begin(); it != (a).end(); it++)
#define sz(a) int((a).size())
#define pconent(t, x) (t.find(x) != t.end())
#define all(a) (a).begin(), (a).end()
#define uni(a) (a).erase(unique(all(a)), (a).end())
#define pb push_back
#define pf push_front
//#define mp make_pair
#define fi first
#define se second
#define prec(n) fixed<<setprecision(n)
#define bit(n, i) (((n) >> (i)) & 1)
#define bitcount(n) __builtin_popcountll(n)
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<pi> vii;
const ll MOD =  1e9 + 7;
const int FFTMOD = 1007681537;
const int INF = (int) 1e9;
const ll LINF = (ll) 1e18;
const ld PI = acos((ld) -1);
const ld EPS = 1e-9;
inline ll gcd(ll a, ll b) {ll r; while (b) {r = a % b; a = b; b = r;} return a;}
inline ll lcm(ll a, ll b) {return a / gcd(a, b) * b;}
inline ll fpow(ll n, ll k, int p = MOD) {ll r = 1; for (; k; k >>= 1) {if (k & 1) r = r * n % p; n = n * n % p;} return r;}
template<class T> inline int chkmin(T& a, const T& val) {return val < a ? a = val, 1 : 0;}
template<class T> inline int chkmax(T& a, const T& val) {return a < val ? a = val, 1 : 0;}
inline ll isqrt(ll k) {ll r = sqrt(k) + 1; while (r * r > k) r--; return r;}
inline ll icbrt(ll k) {ll r = cbrt(k) + 1; while (r * r * r > k) r--; return r;}
inline void addmod(int& a, int val, int p = MOD) {if ((a = (a + val)) >= p) a -= p;}
inline void submod(int& a, int val, int p = MOD) {if ((a = (a - val)) < 0) a += p;}
inline int mult(int a, int b, int p = MOD) {return (ll) a * b % p;}
inline int inv(int a, int p = MOD) {return fpow(a, p - 2, p);}
inline int sign(ld x) {return x < -EPS ? -1 : x > +EPS;}
inline int sign(ld x, ld y) {return sign(x - y);}
#define db(x) cerr << #x << " = " << (x) << " "<<"\n";
#define endln cerr << "\n";
const ll MN = 1e5+10 ;
vector<ll> g [MN] ;
vector<ll> dis [MN] ;
ll color[MN] ;
ll vis[MN] ;
ll fin[MN] ;
bool DFSUtil(int u)
{
    color[u] = 1 ;
    for (ll temp : g[u])
    {
    	int v = (int)temp ;
        // If there is
        if (color[v] == 1)
          return true;
 
        // If v is not processed and there is a back
        // edge in subtree rooted with v
        if (color[v] == 0 && DFSUtil(v))
          return true;
    }
    // Mark this vertex as processed
    color[u] = 2;
    return false;
}
// Returns true if there is a cycle in graph
bool isCyclic()
{
    for (int i = 0; i < MN; i++)
        color[i] = 0;
    for (int i = 0; i < MN; i++)
        if (color[i] == 0)
           if (DFSUtil(i) == true)
              return true;
    return false;
}
void calc(ll u,ll d)
{
	vis[u] = 1 ;
	fin[u] = d ;
	FOR(i,0,g[u].size())
	{
		if(vis[g[u][i]]==0)
		{
			calc(g[u][i],d+dis[u][i]) ;
		}
	}
}
void output()
{
	ll n,m ;
	cin>>n>>m ;
	FOR(i,0,m)
	{
		ll u,v,x ;
		cin>>u>>v>>x ;
		u-- ;v-- ;
		g[u].pb(v) ;
		dis[u].pb(x) ;
	}
	if(isCyclic())
	{
		cout<<"No"<<endl ;
	}
	else
	{
		ll deg[n] ;
		FOR(i,0,n)
		{
			deg[i] = 0 ;
			vis[i] = 0 ;
		}
		FOR(i,0,n)
		{
			for(ll x : g[i])
			{
				deg[x]++ ;
			}
		}
		FOR(i,0,n)
		{
			if(deg[i]==0)
			{
				calc(i,0) ;
			}
		}
		FOR(i,0,n)
		{
			FOR(j,0,g[i].size())
			{
				if(fin[g[i][j]]-fin[i]!=(dis[i][j]))
				{
					cout<<"No"<<endl ;
					return ;
				}
			}
		}
		cout<<"Yes"<<endl ;
	}
}
int main()
{
	 #ifdef LOCAL_PROJECT
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif	
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    ll t  =1;
    FOR(i,0,t)
    {
        output() ;
    }
    return 0 ;
}

Measured memory_bytes: 19072