#ifdef _MSC_VER
#pragma warning(disable : 4996)
#include <intrin.h>
#define __builtin_popcount __popcnt
#endif

#include <limits.h>
#include <math.h>
#include <time.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPR(i, n) for (int i = n - 1; i >= 0; --i)
#define FOR(i, m, n) for (int i = m; i < n; ++i)
#define FORR(i, m, n) for (int i = m - 1; i >= n; --i)
#define SORT(v, n) sort(v, v + n);
#define VSORT(v) sort(v.begin(), v.end());
#define REVERSE(v, n) reverse(v, v + n);
#define VREVERSE(v) reverse(v.begin(), v.end())
#define ll long long
#define print(x) cout << (x) << '\n'
#define pe(x) cout << (x) << " "
#define DEBUG(x) cout << #x << ": " << x << endl
#define lb(v, n) lower_bound(v.begin(), v.end(), (n))
#define ub(v, n) upper_bound(v.begin(), v.end(), (n))
#define int long long
//#define double long double
#define all(x) (x).begin(), (x).end()
#define print_space(v) REP(i, v.size()) cout << v[i] << ((i == v.size() - 1) ? "\n" : " ")
template <typename T1, typename T2> inline void chmin(T1& a, T2 b) {
	if (a > b) a = b;
}
template <typename T1, typename T2> inline void chmax(T1& a, T2 b) {
	if (a < b) a = b;
}
typedef pair<int, int> pii;
typedef array<int, 3> arr3;
std::random_device rd;
std::mt19937 mt(rd());
constexpr ll MOD = 1e9 + 7;
constexpr int MAX = 200020;
const double pi = acos(-1);
constexpr double EPS = 1e-8;
constexpr ll INF = 1e18;

typedef int Weight;
struct Edge {
	int src, dst;
	Weight weight;
	Edge(int src, int dst, Weight weight) :
		src(src), dst(dst), weight(weight) { }
};
bool operator < (const Edge &e, const Edge &f) {
	return e.weight != f.weight ? e.weight > f.weight : // !!INVERSE!!
	e.src != f.src ? e.src < f.src : e.dst < f.dst;
}
typedef vector<Edge> Edges;
typedef vector<Edges> Graph;

typedef vector<Weight> Array;
typedef vector<Array> Matrix;

bool visit(const Graph &g, int v, vector<int> &order, vector<int> &color) {
	color[v] = 1;
	for(auto e: g[v]) {
		if (color[e.dst] == 2) continue;
		if (color[e.dst] == 1) return false;
		if (!visit(g, e.dst, order, color)) return false;
	}
	order.push_back(v); color[v] = 2;
	return true;
}
bool topologicalSort(const Graph &g, vector<int> &order) {
	int n = g.size();
	vector<int> color(n);
	REP(u, n) if (!color[u] && !visit(g, u, order, color))
		return false;
	reverse(all(order));
	return true;
}


bool done[100010];
int pos[100010];
void no() {
	cout << "No" << endl;
	exit(0);
}

void solve() {
	int N, M; cin >> N >> M;
	Graph G;
	G.resize(N);
	REP(i, M) {
		int l, r, d; cin >> l >> r >> d;
		l--, r--;
		G[l].push_back({ l,r,d });
	}
	vector<int>order;
	if (!topologicalSort(G, order))no();
	for(auto i:order) {
		for (auto e : G[i]) {
			int nxt = e.dst;
			int d = e.weight;
			if (done[i] && done[nxt]) {
				if (pos[nxt] - pos[i] != e.weight)no();
			}
			else if (done[nxt]) {
				done[i] = true;
				pos[i] = pos[nxt] - d;
			}
			else if (done[i]) {
				done[nxt] = true;
				pos[nxt] = pos[i] + d;
			}
			else {
				done[i] = done[nxt] = true;
				pos[i] = 0;
				pos[nxt] = pos[i] + d;
			}
		}
	}
	print("Yes");
}

signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	// int q; cin >> q;
	// while (q--)
	solve();
}


Measured memory_bytes: 13688