Problem:
Score : 500 points

Problem Statement

You have a string S of length N.
Initially, all characters in S are 1s.

You will perform queries Q times.
In the i-th query, you are given two integers L_i, R_i and a character D_i (which is a digit).
Then, you must replace all characters from the L_i-th to the R_i-th (inclusive) with D_i.

After each query, read the string S as a decimal integer, and print its value modulo 998,244,353.

Constraints

1 \leq N, Q \leq 200,000

1 \leq L_i \leq R_i \leq N

1 \leq D_i \leq 9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N Q
L_1 R_1 D_1
:
L_Q R_Q D_Q

Output

Print Q lines.
In the i-th line print the value of S after the i-th query, modulo 998,244,353.

Sample Input 1

8 5
3 6 2
1 4 7
3 8 3
2 2 2
4 5 1

Sample Output 1

11222211
77772211
77333333
72333333
72311333

Sample Input 2

200000 1
123 456 7

Sample Output 2

641437905

Don't forget to take the modulo.

Solution in Rust (1.42.0) (judge verdict: Accepted)

// ---------- begin Lazy Segment Tree ----------
pub trait TE {
    type T: Clone;
    type E: Clone;
    fn fold(l: &Self::T, r: &Self::T) -> Self::T;
    fn eval(x: &Self::T, f: &Self::E) -> Self::T;
    fn merge(g: &Self::E, h: &Self::E) -> Self::E;
    fn e() -> Self::T;
    fn id() -> Self::E;
}

pub struct LazySegmentTree<R: TE> {
    size: usize,
    bit: usize,
    a: Vec<(R::T, R::E)>,
}

impl <R: TE> LazySegmentTree<R> {
    pub fn new(n: usize) -> LazySegmentTree<R> {
        let size = n.next_power_of_two();
        let bit = size.trailing_zeros() as usize;
        LazySegmentTree {
            size: size,
            bit: bit,
            a: vec![(R::e(), R::id()); 2 * size],
        }
    }
    pub fn build_by(z: &[R::T]) -> LazySegmentTree<R> {
        let mut seg = LazySegmentTree::<R>::new(z.len());
        for (a, z) in seg.a[seg.size..].iter_mut().zip(z.iter()) {
            a.0 = z.clone();
        }
        let a = &mut seg.a;
        for i in (1..seg.size).rev() {
            a[i].0 = R::fold(&a[2 * i].0, &a[2 * i + 1].0);
        }
        seg
    }
    fn apply(&mut self, x: usize, op: &R::E) {
        let node = &mut self.a[x];
        node.0 = R::eval(&node.0, op);
        node.1 = R::merge(&node.1, op);
    }
    fn propagate(&mut self, x: usize) {
        let mut op = R::id();
        std::mem::swap(&mut op, &mut self.a[x].1);
        self.apply(2 * x, &op);
        self.apply(2 * x + 1, &op);
    }
    fn propagate_range(&mut self, l: usize, r: usize) {
        let x = l + self.size;
        let y = r + self.size;
        let mut k = self.bit;
        while (x >> k) == (y >> k) {
            self.propagate(x >> k);
            k -= 1;
        }
        for i in ((x.trailing_zeros() as usize + 1)..=k).rev() {
            self.propagate(x >> i);
        }
        for i in ((y.trailing_zeros() as usize + 1)..=k).rev() {
            self.propagate(y >> i);
        }
    }
    fn save_range(&mut self, l: usize, r: usize) {
        let mut x = l + self.size;
        let mut y = r + self.size;
        let mut p = (x & 1) == 1;
        let mut q = (y & 1) == 1;
        x >>= 1;
        y >>= 1;
        while 0 < x && x < y {
            if p {
                self.a[x].0 = R::fold(&self.a[2 * x].0, &self.a[2 * x + 1].0);
            }
            if q {
                self.a[y].0 = R::fold(&self.a[2 * y].0, &self.a[2 * y + 1].0);
            }
            p |= (x & 1) == 1;
            q |= (y & 1) == 1;
            x >>= 1;
            y >>= 1;
        }
        while 0 < x {
            self.a[x].0 = R::fold(&self.a[2 * x].0, &self.a[2 * x + 1].0);
            x >>= 1;
        }
    }
    pub fn update(&mut self, l: usize, r: usize, op: R::E) {
        self.propagate_range(l, r);
        let mut x = l + self.size;
        let mut y = r + self.size;
        while x < y {
            if x & 1 == 1 {
                self.apply(x, &op);
                x += 1;
            }
            if y & 1 == 1 {
                y -= 1;
                self.apply(y, &op);
            }
            x >>= 1;
            y >>= 1;
        }
        self.save_range(l, r);
    }
    pub fn find(&mut self, l: usize, r: usize) -> R::T {
        self.propagate_range(l, r);
        let mut x = l + self.size;
        let mut y = r + self.size;
        let mut p = R::e();
        let mut q = R::e();
        while x < y {
            if x & 1 == 1 {
                p = R::fold(&p, &self.a[x].0);
                x += 1;
            }
            if y & 1 == 1 {
                y -= 1;
                q = R::fold(&self.a[y].0, &q);
            }
            x >>= 1;
            y >>= 1;
        }
        R::fold(&p, &q)
    }
}
// ---------- end Lazy Segment Tree ----------
// ---------- begin ModInt ----------
mod modint {

    #[allow(dead_code)]
    pub struct Mod;
    impl ConstantModulo for Mod {
        const MOD: u32 = 998_244_353;
    }

    #[allow(dead_code)]
    pub struct StaticMod;
    static mut STATIC_MOD: u32 = 0;
    impl Modulo for StaticMod {
        fn modulo() -> u32 {
            unsafe { STATIC_MOD }
        }
    }

    #[allow(dead_code)]
    impl StaticMod {
        pub fn set_modulo(p: u32) {
            unsafe {
                STATIC_MOD = p;
            }
        }
    }

    use std::marker::*;
    use std::ops::*;

    pub trait Modulo {
        fn modulo() -> u32;
    }

    pub trait ConstantModulo {
        const MOD: u32;
    }

    impl<T> Modulo for T
    where
        T: ConstantModulo,
    {
        fn modulo() -> u32 {
            T::MOD
        }
    }

    pub struct ModInt<T>(pub u32, PhantomData<T>);

    impl<T> Clone for ModInt<T> {
        fn clone(&self) -> Self {
            ModInt::new_unchecked(self.0)
        }
    }

    impl<T> Copy for ModInt<T> {}

    impl<T: Modulo> Add for ModInt<T> {
        type Output = ModInt<T>;
        fn add(self, rhs: Self) -> Self::Output {
            let mut d = self.0 + rhs.0;
            if d >= T::modulo() {
                d -= T::modulo();
            }
            ModInt::new_unchecked(d)
        }
    }

    impl<T: Modulo> AddAssign for ModInt<T> {
        fn add_assign(&mut self, rhs: Self) {
            *self = *self + rhs;
        }
    }

    impl<T: Modulo> Sub for ModInt<T> {
        type Output = ModInt<T>;
        fn sub(self, rhs: Self) -> Self::Output {
            let mut d = T::modulo() + self.0 - rhs.0;
            if d >= T::modulo() {
                d -= T::modulo();
            }
            ModInt::new_unchecked(d)
        }
    }

    impl<T: Modulo> SubAssign for ModInt<T> {
        fn sub_assign(&mut self, rhs: Self) {
            *self = *self - rhs;
        }
    }

    impl<T: Modulo> Mul for ModInt<T> {
        type Output = ModInt<T>;
        fn mul(self, rhs: Self) -> Self::Output {
            let v = self.0 as u64 * rhs.0 as u64 % T::modulo() as u64;
            ModInt::new_unchecked(v as u32)
        }
    }

    impl<T: Modulo> MulAssign for ModInt<T> {
        fn mul_assign(&mut self, rhs: Self) {
            *self = *self * rhs;
        }
    }

    impl<T: Modulo> Neg for ModInt<T> {
        type Output = ModInt<T>;
        fn neg(self) -> Self::Output {
            if self.0 == 0 {
                Self::zero()
            } else {
                Self::new_unchecked(T::modulo() - self.0)
            }
        }
    }

    impl<T> std::fmt::Display for ModInt<T> {
        fn fmt<'a>(&self, f: &mut std::fmt::Formatter<'a>) -> std::fmt::Result {
            write!(f, "{}", self.0)
        }
    }

    impl<T: Modulo> std::str::FromStr for ModInt<T> {
        type Err = std::num::ParseIntError;
        fn from_str(s: &str) -> Result<Self, Self::Err> {
            let val = s.parse::<u32>()?;
            Ok(ModInt::new(val))
        }
    }

    impl<T: Modulo> From<usize> for ModInt<T> {
        fn from(val: usize) -> ModInt<T> {
            ModInt::new_unchecked((val % T::modulo() as usize) as u32)
        }
    }

    impl<T: Modulo> From<u64> for ModInt<T> {
        fn from(val: u64) -> ModInt<T> {
            ModInt::new_unchecked((val % T::modulo() as u64) as u32)
        }
    }

    impl<T: Modulo> From<i64> for ModInt<T> {
        fn from(val: i64) -> ModInt<T> {
            let m = T::modulo() as i64;
            ModInt::new((val % m + m) as u32)
        }
    }

    #[allow(dead_code)]
    impl<T> ModInt<T> {
        pub fn new_unchecked(d: u32) -> Self {
            ModInt(d, PhantomData)
        }
        pub fn zero() -> Self {
            ModInt::new_unchecked(0)
        }
        pub fn one() -> Self {
            ModInt::new_unchecked(1)
        }
        pub fn is_zero(&self) -> bool {
            self.0 == 0
        }
    }

    #[allow(dead_code)]
    impl<T: Modulo> ModInt<T> {
        pub fn new(d: u32) -> Self {
            ModInt::new_unchecked(d % T::modulo())
        }
        pub fn pow(&self, mut n: u64) -> Self {
            let mut t = Self::one();
            let mut s = *self;
            while n > 0 {
                if n & 1 == 1 {
                    t *= s;
                }
                s *= s;
                n >>= 1;
            }
            t
        }
        pub fn inv(&self) -> Self {
            assert!(self.0 != 0);
            self.pow(T::modulo() as u64 - 2)
        }
    }

    #[allow(dead_code)]
    pub fn mod_pow(r: u64, mut n: u64, m: u64) -> u64 {
        let mut t = 1 % m;
        let mut s = r % m;
        while n > 0 {
            if n & 1 == 1 {
                t = t * s % m;
            }
            s = s * s % m;
            n >>= 1;
        }
        t
    }
}
// ---------- end ModInt ----------
// ---------- begin Precalc ----------
mod precalc {
    use super::modint::*;
    #[allow(dead_code)]
    pub struct Precalc<T> {
        inv: Vec<ModInt<T>>,
        fact: Vec<ModInt<T>>,
        ifact: Vec<ModInt<T>>,
    }
    #[allow(dead_code)]
    impl<T: Modulo> Precalc<T> {
        pub fn new(n: usize) -> Precalc<T> {
            let mut inv = vec![ModInt::one(); n + 1];
            let mut fact = vec![ModInt::one(); n + 1];
            let mut ifact = vec![ModInt::one(); n + 1];
            for i in 2..(n + 1) {
                fact[i] = fact[i - 1] * ModInt::new_unchecked(i as u32);
            }
            ifact[n] = fact[n].inv();
            if n > 0 {
                inv[n] = ifact[n] * fact[n - 1];
            }
            for i in (1..n).rev() {
                ifact[i] = ifact[i + 1] * ModInt::new_unchecked((i + 1) as u32);
                inv[i] = ifact[i] * fact[i - 1];
            }
            Precalc {
                inv: inv,
                fact: fact,
                ifact: ifact,
            }
        }
        pub fn inv(&self, n: usize) -> ModInt<T> {
            assert!(n > 0);
            self.inv[n]
        }
        pub fn fact(&self, n: usize) -> ModInt<T> {
            self.fact[n]
        }
        pub fn ifact(&self, n: usize) -> ModInt<T> {
            self.ifact[n]
        }
        pub fn perm(&self, n: usize, k: usize) -> ModInt<T> {
            if k > n {
                return ModInt::zero();
            }
            self.fact[n] * self.ifact[n - k]
        }
        pub fn comb(&self, n: usize, k: usize) -> ModInt<T> {
            if k > n {
                return ModInt::zero();
            }
            self.fact[n] * self.ifact[k] * self.ifact[n - k]
        }
    }
}
// ---------- end Precalc ----------

use proconio::*;
use proconio::marker::*;

use modint::*;
type M = ModInt<Mod>;

struct R;
impl TE for R {
    type T = (M, M);
    type E = Option<M>;
    fn fold(l: &Self::T, r: &Self::T) -> Self::T {
        (l.0 * r.1 + r.0, l.1 * r.1)
    }
    fn eval(x: &Self::T, f: &Self::E) -> Self::T {
        if let Some(d) = *f {
            (d * (x.1 - M::one()) * M::new(9).inv(), x.1)
        } else {
            *x
        }
    }
    fn merge(g: &Self::E, h: &Self::E) -> Self::E {
        if h.is_some() {
            *h
        } else {
            *g
        }
    }
    fn e() -> Self::T {
        (M::zero(), M::one())
    }
    fn id() -> Self::E {
        None
    }
}

#[fastout]
fn run() {
    input! {
        n: usize,
        q: usize,
        ask: [(Usize1, usize, M); q],
    }
    let ini = vec![(M::one(), M::new(10)); n];
    let mut seg = LazySegmentTree::<R>::build_by(&ini);
    for (l, r, d) in ask {
        seg.update(l, r, Some(d));
        let ans = seg.find(0, n).0;
        println!("{}", ans);
    }
}

fn main() {
    run();
}