// ---------- begin Centroid Decomposition ----------
struct CentroidDecomposition {
    graph: Vec<Vec<usize>>,
    next: Vec<(usize, usize)>,
}

#[allow(dead_code)]
impl CentroidDecomposition {
    fn new(n: usize) -> Self {
        CentroidDecomposition {
            graph: vec![vec![]; n],
            next: vec![],
        }
    }
    fn add_edge(&mut self, a: usize, b: usize) {
        self.graph[a].push(b);
        self.graph[b].push(a);
    }
    fn build(&mut self) {
        let graph = &self.graph;
        let next = &mut self.next;
        let n = graph.len();
        next.clear();
        next.resize(n, (n, n));
        assert!(
            graph.iter().fold(0, |s, a| s + a.len()) == 2 * n - 2,
            "graph is not tree"
        );
        let mut dfs = vec![(0, 0, n)];
        let mut used = vec![false; n];
        let mut size = vec![0; n];
        let mut stack = vec![];
        let mut q = vec![];
        while let Some((v, rank, g)) = dfs.pop() {
            size[v] = 0;
            stack.push((v, v));
            q.clear();
            while let Some((v, p)) = stack.pop() {
                q.push(v);
                for &u in graph[v].iter() {
                    size[u] = 0;
                    if u != p && !used[u] {
                        stack.push((u, v));
                    }
                }
            }
            for &v in q.iter().rev() {
                size[v] = 1;
                for &u in graph[v].iter() {
                    size[v] += size[u];
                }
            }
            let mut parent = v;
            let mut r = v;
            loop {
                let mut max = (0, 0);
                for &u in graph[r].iter() {
                    if u != parent && !used[u] {
                        max = std::cmp::max(max, (size[u], u));
                    }
                }
                if 2 * max.0 <= size[v] {
                    break;
                }
                parent = r;
                r = max.1;
            }
            used[r] = true;
            next[r] = (rank, g);
            for &v in graph[r].iter() {
                if !used[v] {
                    dfs.push((v, rank + 1, r));
                }
            }
        }
    }
    fn belong(&self, v: usize) -> Vec<usize> {
        let mut ans = vec![];
        let mut v = v;
        while v < self.graph.len() {
            ans.push(v);
            v = self.next[v].1;
        }
        ans
    }
    fn rank(&self, v: usize) -> usize {
        self.next[v].0
    }
}
// ---------- end Centroid Decomposition ----------
// ---------- begin SegmentTree Range update Point query ----------
mod segment_tree {
    pub struct RUPQ<T, F> {
        n: usize,
        b: usize,
        a: Vec<T>,
        id: T,
        op: F,
    }
    impl<T: Copy, F: Fn(T, T) -> T> RUPQ<T, F> {
        pub fn new(n: usize, id: T, op: F) -> RUPQ<T, F> {
            let mut k = 0;
            while (1 << k) < n {
                k += 1;
            }
            RUPQ {
                n: 1 << k,
                b: k,
                a: vec![id; 2 << k],
                id: id,
                op: op,
            }
        }
        fn down(&mut self, x: usize) {
            let k = x + self.n;
            let a = &mut self.a;
            for i in (1..(self.b + 1)).rev() {
                let y = k >> i;
                a[2 * y] = (self.op)(a[2 * y], a[y]);
                a[2 * y + 1] = (self.op)(a[2 * y + 1], a[y]);
                a[y] = self.id;
            }
        }
        pub fn update(&mut self, mut l: usize, mut r: usize, v: T) {
            self.down(l);
            self.down(r - 1);
            l += self.n;
            r += self.n;
            let a = &mut self.a;
            while l < r {
                if (l & 1) == 1 {
                    a[l] = (self.op)(a[l], v);
                    l += 1;
                }
                if (r & 1) == 1 {
                    r -= 1;
                    a[r] = (self.op)(a[r], v);
                }
                l >>= 1;
                r >>= 1;
            }
        }
        pub fn find(&mut self, mut x: usize) -> T {
            x += self.n;
            let mut y = self.a[x];
            x >>= 1;
            while x > 0 {
                y = (self.op)(y, self.a[x]);
                x >>= 1;
            }
            y
        }
    }
}
// ---------- end SegmentTree Range update Point query ----------
//https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 より
macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let 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")
    };
}

//

use std::io::Write;

fn run() {
    input! {
        n: usize,
        q: usize,
        e: [(usize1, usize1); n - 1],
        ask: [(usize1, usize, i64); q],
    }
    let mut cent = CentroidDecomposition::new(n);
    for (a, b) in e {
        cent.add_edge(a, b);
    }
    cent.build();
    let mut memo = vec![];
    let mut max_rank = 0;
    for rank in 0.. {
        let mut update = false;
        let mut dp = vec![std::usize::MAX; n];
        for v in 0..n {
            if cent.rank(v) != rank {
                continue;
            }
            update = true;
            dp[v] = 0;
            let mut stack = vec![(v, v)];
            while let Some((v, p)) = stack.pop() {
                let d = dp[v] + 1;
                for &u in cent.graph[v].iter() {
                    if u != p && cent.rank(u) > rank {
                        dp[u] = d;
                        stack.push((u, v));
                    }
                }
            }
        }
        if update {
            memo.push(dp);
            max_rank = rank;
        } else {
            break;
        }
    }
    max_rank += 1;
    let mut add = vec![];
    let mut sub = vec![];
    for i in 0..n {
        let r = cent.rank(i);
        let size = 1 << (max_rank - r);
        add.push(segment_tree::RUPQ::new(size, 0, |a, b| a + b));
        sub.push(segment_tree::RUPQ::new(size, 0, |a, b| a + b));
    }
    let out = std::io::stdout();
    let mut out = std::io::BufWriter::new(out.lock());
    for (x, y, z) in ask {
        let mut ans = 0;
        let mut belong = cent.belong(x);
        belong.reverse();
        for (&g, memo) in belong.iter().zip(memo.iter()) {
            let d = memo[x];
            ans += add[g].find(d);
        }
        for (&g, memo) in belong.iter().skip(1).zip(memo.iter()) {
            let d = memo[x];
            ans -= sub[g].find(d);
        }
        writeln!(out, "{}", ans).ok();
        for (i, (&g, memo)) in belong.iter().zip(memo.iter()).enumerate() {
            let d = memo[x];
            if y >= d {
                let r = std::cmp::min(y - d + 1, 1 << (max_rank - i));
                add[g].update(0, r, z);
            }
        }
        for (i, (&g, memo)) in belong.iter().skip(1).zip(memo.iter()).enumerate() {
            let d = memo[x];
            if y >= d {
                let r = std::cmp::min(y - d + 1, 1 << (max_rank - i - 1));
                sub[g].update(0, r, z);
            }
        }
    }
}

fn main() {
    run();
}