macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let mut s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}
 
macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};
 
    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}
 
macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };
 
    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };
 
    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };
 
    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };
 
    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}
fn main() {
    input!{
        n: i32,
        m: i32,
        lrd:[[i32;3];m]
    }
    let mut lrd = lrd;
    let mut offsets:Vec<Option<i32>> = vec!();
    offsets.resize(n as usize,None);
    lrd.sort_by(|a,b|a[0].cmp(&b[0]));
    for c in lrd {
        let l = (c[0]-1) as usize;
        let r = (c[1]-1) as usize;
        let d = c[2];
 
        let ol = offsets[l];
        let or = offsets[r];
        if ol != None && or  != None {
            //validation
            if (or.unwrap() - ol.unwrap()) != d {
                println!("No");
                std::process::exit(0);
            }
        }
        else if ol  != None {
         offsets[r] = Some(ol.unwrap() + d);
        }
        else if or  != None {
         offsets[l] = Some(or.unwrap() - d);
        }
        else{
         offsets[l] = Some(0);
         offsets[r] = Some(d);
        }
        
    }
    println!("Yes");
}