import core.bitop, std.algorithm, std.ascii, std.bigint, std.conv, std.math,
    std.functional, std.numeric, std.range, std.stdio, std.string, std.random,
    std.typecons, std.container, std.format;
static import std.ascii;

// dfmt off
T lread(T = long)(){return readln.chomp.to!T();}
T[] lreads(T = long)(long n){return generate(()=>readln.chomp.to!T()).take(n).array();}
T[] aryread(T = long)(){return readln.split.to!(T[])();}
void scan(TList...)(ref TList Args){auto line = readln.split();
foreach (i, T; TList){T val = line[i].to!(T);Args[i] = val;}}
alias sread = () => readln.chomp();enum MOD = 10 ^^ 9 + 7;
alias PQueue(T, alias less = "a<b") = BinaryHeap!(Array!T, less);
// dfmt on

void main()
{
    long N, M;
    scan(N, M);
    alias T = Tuple!(long, long);
    auto G = new T[][](N);
    alias T2 = Tuple!(long, long, long);
    auto LRD = new T2[](M);
    foreach (i; 0 .. M)
    {
        long L, R, D;
        scan(L, R, D);
        L--, R--;
        LRD[i] = T2(L, R, D);
        G[R] ~= T(L, D);
    }
    auto pos = new long[](N);
    pos[] = -2;
    long eval(long x)
    {
        // writefln("%s %s", x, G[x]);
        if (pos[x] == -1)
            return 0;
        if (pos[x] == -2)
        {
            pos[x] = -1;
            if (G[x].length == 0)
            {
                pos[x] = 0;
                return 0;
            }
            long d;
            foreach (t; G[x])
            {
                d = max(d, t[1] + eval(t[0]));
            }
            pos[x] = d;
            return d;
        }
        else
        {
            return pos[x];
        }
    }

    foreach (i; 0 .. N)
        eval(i);

    foreach (lrd; LRD)
    {
        if (pos[lrd[1]] - pos[lrd[0]] != lrd[2])
        {
            writeln("No");
            return;
        }
    }
    writeln("Yes");

    // writeln(pos);
}
