Problem:
 Score : 500 points    Problem Statement You have a string S of length N .
Initially, all characters in S are 1 s.  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 (Python):
class LazySegmentTree():

    def __init__(self, n, f, g, h, ef, eh):
        """
        :param n: 配列の要素数
        :param f: 取得半群の元同士の積を定義
        :param g: 更新半群の元 xh が配列上の実際の値にどのように作用するかを定義
        :param h: 更新半群の元同士の積を定義　（更新半群の元を xh と表記）
        :param x: 配列の各要素の値。treeの葉以外は xf(x1,x2,...)
        """
        self.n = n
        self.f = f
        self.g = lambda xh, x: g(xh, x) if xh != eh else x
        self.h = h
        self.ef = ef
        self.eh = eh
        l = (self.n - 1).bit_length()
        self.size = 1 << l
        self.tree = [self.ef] * (self.size << 1)
        self.lazy = [self.eh] * ((self.size << 1) + 1)
        self.plt_cnt = 0

    def built(self, array):
        """
        arrayを初期値とするセグメント木を構築
        """
        for i in range(self.n):
            self.tree[self.size + i] = array[i]
        for i in range(self.size - 1, 0, -1):
            self.tree[i] = self.f(self.tree[i<<1], self.tree[(i<<1)|1])

    def update(self, i, x):
        """
        i 番目の要素を x に更新する
        """
        i += self.size
        self.propagate_lazy(i)
        self.tree[i] = x
        self.lazy[i] = self.eh
        self.propagate_tree(i)

    def get(self, i):
        """
        i 番目の値を取得（ 0-indexed ） ( O(logN) )
        """
        i += self.size
        self.propagate_lazy(i)
        return self.g(self.lazy[i], self.tree[i])

    def update_range(self, l, r, x):
        """
        半開区間 [l, r) の各々の要素 a に op(x, a)を作用させる （ 0-indexed ）　（ O(logN) ）
        """
        if l >= r:
            return
        l += self.size
        r += self.size
        l0 = l//(l&-l)
        r0 = r//(r&-r)
        self.propagate_lazy(l0)
        self.propagate_lazy(r0-1)
        while l < r:
            if r&1:
                r -= 1              
                self.lazy[r] = self.h(x, self.lazy[r])
            if l&1:
                self.lazy[l] = self.h(x, self.lazy[l])
                l += 1
            l >>= 1
            r >>= 1
        self.propagate_tree(l0)
        self.propagate_tree(r0-1)

    def get_range(self, l, r):
        """
        [l, r)への作用の結果を返す　(0-indexed)
        """
        l += self.size
        r += self.size
        self.propagate_lazy(l//(l&-l))
        self.propagate_lazy((r//(r&-r))-1)
        res_l = self.ef
        res_r = self.ef
        while l < r:
            if l & 1:
                res_l = self.f(res_l, self.g(self.lazy[l], self.tree[l]))
                l += 1
            if r & 1:
                r -= 1
                res_r = self.f(self.g(self.lazy[r], self.tree[r]), res_r)
            l >>= 1
            r >>= 1
        return self.f(res_l, res_r)

    def max_right(self, l, z):
        """
        以下の条件を両方満たす r を(いずれか一つ)返す
            ・r = l or f(op(a[l], a[l + 1], ..., a[r - 1])) = true
            ・r = n or f(op(a[l], a[l + 1], ..., a[r])) = false
        """
        if l >= self.n: return self.n
        l += self.size
        s = self.ef
        while 1:
            while l % 2 == 0:
                l >>= 1
            if not z(self.f(s, self.g(self.lazy[l], self.tree[l]))):
                while l < self.size:
                    l *= 2
                    if z(self.f(s, self.g(self.lazy[l], self.tree[l]))):
                        s = self.f(s, self.g(self.lazy[l], self.tree[l]))
                        l += 1
                return l - self.size
            s = self.f(s, self.g(self.lazy[l], self.tree[l]))
            l += 1
            if l & -l == l: break
        return self.n

    def min_left(self, r, z):
        """
        以下の条件を両方満たす l を(いずれか一つ)返す
            ・l = r or f(op(a[l], a[l + 1], ..., a[r - 1])) = true
            ・l = 0 or f(op(a[l - 1], a[l], ..., a[r - 1])) = false
        """
        if r <= 0: return 0
        r += self.size
        s = self.ef
        while 1:
            r -= 1
            while r > 1 and r % 2:
                r >>= 1
            if not z(self.f(self.g(self.lazy[r], self.tree[r]), s)):
                while r < self.size:
                    r = r * 2 + 1
                    if z(self.f(self.g(self.lazy[r], self.tree[r]), s)):
                        s = self.f(self.g(self.lazy[r], self.tree[r]), s)
                        r -= 1
                return r + 1 - self.size
            s = self.f(self.g(self.lazy[r], self.tree[r]), s)
            if r & -r == r: break
        return 0

    def propagate_lazy(self, i):
        """
        lazy の値をトップダウンで更新する　（ O(logN) ）
        """
        for k in range(i.bit_length()-1,0,-1):
            x = i>>k
            if self.lazy[x] == self.eh:
                continue
            laz = self.lazy[x]
            self.lazy[(x<<1)|1] = self.h(laz, self.lazy[(x<<1)|1])
            self.lazy[x<<1] = self.h(laz, self.lazy[x<<1])
            self.tree[x] = self.g(laz, self.tree[x])   
            self.lazy[x] = self.eh


    def propagate_tree(self, i):
        """
        tree の値をボトムアップで更新する　（ O(logN) ）
        """
        while i>1:
            i>>=1
            self.tree[i] = self.f(self.g(self.lazy[i<<1], self.tree[i<<1]), self.g(self.lazy[(i<<1)|1], self.tree[(i<<1)|1]))

    def __getitem__(self, i):
        return self.get(i)

    def __iter__(self):
        for x in range(1, self.size):
            if self.lazy[x] == self.eh:
                continue
            self.lazy[(x<<1)|1] = self.h(self.lazy[x], self.lazy[(x<<1)|1])
            self.lazy[x<<1] = self.h(self.lazy[x], self.lazy[x<<1])
            self.tree[x] = self.g(self.lazy[x], self.tree[x])
            self.lazy[x] = self.eh
        for xh, x in zip(self.lazy[self.size:self.size+self.n], self.tree[self.size:self.size+self.n]):
            yield self.g(xh,x)

    def __str__(self):
        return str(list(self))



from itertools import accumulate
import sys
input = sys.stdin.readline

MOD = 998244353
off = 22
mask = 1<<22

N, Q = map(int, input().split())

P = [pow(10,p,MOD) for p in range(N+1)]
SP = [0]
for p in P:
    SP.append((SP[-1]+p)%MOD)

ef = 0
def f(x, y):
    x0, x1 = x>>off, x%mask
    y0, y1 = y>>off, y%mask
    res = x0*P[y1]+y0
    res %= MOD
    return (res<<off) + x1+y1

eh = -1
def h(a,b):
    return a if a != eh else b

def g(a, x):
    x1 = x%mask
    res = a*SP[x1]%MOD
    return (res<<off) + x1

st = LazySegmentTree(N, f, g, h, ef, eh)

st.built([(1<<off) + 1]*N)
res = [""]*Q
for i in range(Q):
    L, R, D = map(int, input().split())
    st.update_range(L-1, R, D)
    res[i] = str((st.get_range(0,N)>>off)%MOD)
print("\n".join(res))

Solution (Python):
class LazySegmentTree():

    def __init__(self, n, f, g, h, ef, eh):
        """
        :param n: 配列の要素数
        :param f: 取得半群の元同士の積を定義
        :param g: 更新半群の元 xh が配列上の実際の値にどのように作用するかを定義
        :param h: 更新半群の元同士の積を定義　（更新半群の元を xh と表記）
        :param x: 配列の各要素の値。treeの葉以外は xf(x1,x2,...)
        """
        self.n = n
        self.f = f
        self.g = lambda xh, x: g(xh, x) if xh != eh else x
        self.h = h
        self.ef = ef
        self.eh = eh
        l = (self.n - 1).bit_length()
        self.size = 1 << l
        self.tree = [self.ef] * (self.size << 1)
        self.lazy = [self.eh] * ((self.size << 1) + 1)
        self.plt_cnt = 0

    def built(self, array):
        """
        arrayを初期値とするセグメント木を構築
        """
        for i in range(self.n):
            self.tree[self.size + i] = array[i]
        for i in range(self.size - 1, 0, -1):
            self.tree[i] = self.f(self.tree[i<<1], self.tree[(i<<1)|1])

    def update(self, i, x):
        """
        i 番目の要素を x に更新する
        """
        i += self.size
        self.propagate_lazy(i)
        self.tree[i] = x
        self.lazy[i] = self.eh
        self.propagate_tree(i)

    def get(self, i):
        """
        i 番目の値を取得（ 0-indexed ） ( O(logN) )
        """
        i += self.size
        self.propagate_lazy(i)
        return self.g(self.lazy[i], self.tree[i])

    def update_range(self, l, r, x):
        """
        半開区間 [l, r) の各々の要素 a に op(x, a)を作用させる （ 0-indexed ）　（ O(logN) ）
        """
        if l >= r:
            return
        l += self.size
        r += self.size
        l0 = l//(l&-l)
        r0 = r//(r&-r)
        self.propagate_lazy(l0)
        self.propagate_lazy(r0-1)
        while l < r:
            if r&1:
                r -= 1              
                self.lazy[r] = self.h(x, self.lazy[r])
            if l&1:
                self.lazy[l] = self.h(x, self.lazy[l])
                l += 1
            l >>= 1
            r >>= 1
        self.propagate_tree(l0)
        self.propagate_tree(r0-1)

    def get_range(self, l, r):
        """
        [l, r)への作用の結果を返す　(0-indexed)
        """
        l += self.size
        r += self.size
        self.propagate_lazy(l//(l&-l))
        self.propagate_lazy((r//(r&-r))-1)
        res_l = self.ef
        res_r = self.ef
        while l < r:
            if l & 1:
                res_l = self.f(res_l, self.g(self.lazy[l], self.tree[l]))
                l += 1
            if r & 1:
                r -= 1
                res_r = self.f(self.g(self.lazy[r], self.tree[r]), res_r)
            l >>= 1
            r >>= 1
        return self.f(res_l, res_r)

    def max_right(self, l, z):
        """
        以下の条件を両方満たす r を(いずれか一つ)返す
            ・r = l or f(op(a[l], a[l + 1], ..., a[r - 1])) = true
            ・r = n or f(op(a[l], a[l + 1], ..., a[r])) = false
        """
        if l >= self.n: return self.n
        l += self.size
        s = self.ef
        while 1:
            while l % 2 == 0:
                l >>= 1
            if not z(self.f(s, self.g(self.lazy[l], self.tree[l]))):
                while l < self.size:
                    l *= 2
                    if z(self.f(s, self.g(self.lazy[l], self.tree[l]))):
                        s = self.f(s, self.g(self.lazy[l], self.tree[l]))
                        l += 1
                return l - self.size
            s = self.f(s, self.g(self.lazy[l], self.tree[l]))
            l += 1
            if l & -l == l: break
        return self.n

    def min_left(self, r, z):
        """
        以下の条件を両方満たす l を(いずれか一つ)返す
            ・l = r or f(op(a[l], a[l + 1], ..., a[r - 1])) = true
            ・l = 0 or f(op(a[l - 1], a[l], ..., a[r - 1])) = false
        """
        if r <= 0: return 0
        r += self.size
        s = self.ef
        while 1:
            r -= 1
            while r > 1 and r % 2:
                r >>= 1
            if not z(self.f(self.g(self.lazy[r], self.tree[r]), s)):
                while r < self.size:
                    r = r * 2 + 1
                    if z(self.f(self.g(self.lazy[r], self.tree[r]), s)):
                        s = self.f(self.g(self.lazy[r], self.tree[r]), s)
                        r -= 1
                return r + 1 - self.size
            s = self.f(self.g(self.lazy[r], self.tree[r]), s)
            if r & -r == r: break
        return 0

    def propagate_lazy(self, i):
        """
        lazy の値をトップダウンで更新する　（ O(logN) ）
        """
        for k in range(i.bit_length()-1,0,-1):
            x = i>>k
            if self.lazy[x] == self.eh:
                continue
            laz = self.lazy[x]
            self.lazy[(x<<1)|1] = self.h(laz, self.lazy[(x<<1)|1])
            self.lazy[x<<1] = self.h(laz, self.lazy[x<<1])
            self.tree[x] = self.g(laz, self.tree[x])   
            self.lazy[x] = self.eh


    def propagate_tree(self, i):
        """
        tree の値をボトムアップで更新する　（ O(logN) ）
        """
        while i>1:
            i>>=1
            self.tree[i] = self.f(self.g(self.lazy[i<<1], self.tree[i<<1]), self.g(self.lazy[(i<<1)|1], self.tree[(i<<1)|1]))

    def __getitem__(self, i):
        return self.get(i)

    def __iter__(self):
        for x in range(1, self.size):
            if self.lazy[x] == self.eh:
                continue
            self.lazy[(x<<1)|1] = self.h(self.lazy[x], self.lazy[(x<<1)|1])
            self.lazy[x<<1] = self.h(self.lazy[x], self.lazy[x<<1])
            self.tree[x] = self.g(self.lazy[x], self.tree[x])
            self.lazy[x] = self.eh
        for xh, x in zip(self.lazy[self.size:self.size+self.n], self.tree[self.size:self.size+self.n]):
            yield self.g(xh,x)

    def __str__(self):
        return str(list(self))



from itertools import accumulate
import sys
input = sys.stdin.readline

MOD = 998244353
off = 10**7

N, Q = map(int, input().split())

P = [pow(10,p,MOD) for p in range(N+1)]
SP = [0]
for p in P:
    SP.append((SP[-1]+p)%MOD)

ef = 0
def f(x, y):
    x0, x1 = divmod(x,off)
    y0, y1 = divmod(y,off)
    res = x0*P[y1]+y0
    res %= MOD
    return (res*off) + x1+y1

eh = -1
def h(a,b):
    return a if a != eh else b

def g(a, x):
    x1 = x%off
    res = a*SP[x1]%MOD
    return (res*off) + x1

st = LazySegmentTree(N, f, g, h, ef, eh)

st.built([(off) + 1]*N)
res = [""]*Q
for i in range(Q):
    L, R, D = map(int, input().split())
    st.update_range(L-1, R, D)
    res[i] = str((st.get_range(0,N)//off)%MOD)
print("\n".join(res))

Solution (Python):
class LazySegmentTree():

    def __init__(self, n, f, g, h, ef, eh):
        """
        :param n: 配列の要素数
        :param f: 取得半群の元同士の積を定義
        :param g: 更新半群の元 xh が配列上の実際の値にどのように作用するかを定義
        :param h: 更新半群の元同士の積を定義　（更新半群の元を xh と表記）
        :param x: 配列の各要素の値。treeの葉以外は xf(x1,x2,...)
        """
        self.n = n
        self.f = f
        self.g = lambda xh, x: g(xh, x) if xh != eh else x
        self.h = h
        self.ef = ef
        self.eh = eh
        l = (self.n - 1).bit_length()
        self.size = 1 << l
        self.tree = [self.ef] * (self.size << 1)
        self.lazy = [self.eh] * ((self.size << 1) + 1)
        self.plt_cnt = 0

    def built(self, array):
        """
        arrayを初期値とするセグメント木を構築
        """
        for i in range(self.n):
            self.tree[self.size + i] = array[i]
        for i in range(self.size - 1, 0, -1):
            self.tree[i] = self.f(self.tree[i<<1], self.tree[(i<<1)|1])

    def update(self, i, x):
        """
        i 番目の要素を x に更新する
        """
        i += self.size
        self.propagate_lazy(i)
        self.tree[i] = x
        self.lazy[i] = self.eh
        self.propagate_tree(i)

    def get(self, i):
        """
        i 番目の値を取得（ 0-indexed ） ( O(logN) )
        """
        i += self.size
        self.propagate_lazy(i)
        return self.g(self.lazy[i], self.tree[i])

    def update_range(self, l, r, x):
        """
        半開区間 [l, r) の各々の要素 a に op(x, a)を作用させる （ 0-indexed ）　（ O(logN) ）
        """
        if l >= r:
            return
        l += self.size
        r += self.size
        l0 = l//(l&-l)
        r0 = r//(r&-r)
        self.propagate_lazy(l0)
        self.propagate_lazy(r0-1)
        while l < r:
            if r&1:
                r -= 1              
                self.lazy[r] = self.h(x, self.lazy[r])
            if l&1:
                self.lazy[l] = self.h(x, self.lazy[l])
                l += 1
            l >>= 1
            r >>= 1
        self.propagate_tree(l0)
        self.propagate_tree(r0-1)

    def get_range(self, l, r):
        """
        [l, r)への作用の結果を返す　(0-indexed)
        """
        l += self.size
        r += self.size
        self.propagate_lazy(l//(l&-l))
        self.propagate_lazy((r//(r&-r))-1)
        res_l = self.ef
        res_r = self.ef
        while l < r:
            if l & 1:
                res_l = self.f(res_l, self.g(self.lazy[l], self.tree[l]))
                l += 1
            if r & 1:
                r -= 1
                res_r = self.f(self.g(self.lazy[r], self.tree[r]), res_r)
            l >>= 1
            r >>= 1
        return self.f(res_l, res_r)

    def max_right(self, l, z):
        """
        以下の条件を両方満たす r を(いずれか一つ)返す
            ・r = l or f(op(a[l], a[l + 1], ..., a[r - 1])) = true
            ・r = n or f(op(a[l], a[l + 1], ..., a[r])) = false
        """
        if l >= self.n: return self.n
        l += self.size
        s = self.ef
        while 1:
            while l % 2 == 0:
                l >>= 1
            if not z(self.f(s, self.g(self.lazy[l], self.tree[l]))):
                while l < self.size:
                    l *= 2
                    if z(self.f(s, self.g(self.lazy[l], self.tree[l]))):
                        s = self.f(s, self.g(self.lazy[l], self.tree[l]))
                        l += 1
                return l - self.size
            s = self.f(s, self.g(self.lazy[l], self.tree[l]))
            l += 1
            if l & -l == l: break
        return self.n

    def min_left(self, r, z):
        """
        以下の条件を両方満たす l を(いずれか一つ)返す
            ・l = r or f(op(a[l], a[l + 1], ..., a[r - 1])) = true
            ・l = 0 or f(op(a[l - 1], a[l], ..., a[r - 1])) = false
        """
        if r <= 0: return 0
        r += self.size
        s = self.ef
        while 1:
            r -= 1
            while r > 1 and r % 2:
                r >>= 1
            if not z(self.f(self.g(self.lazy[r], self.tree[r]), s)):
                while r < self.size:
                    r = r * 2 + 1
                    if z(self.f(self.g(self.lazy[r], self.tree[r]), s)):
                        s = self.f(self.g(self.lazy[r], self.tree[r]), s)
                        r -= 1
                return r + 1 - self.size
            s = self.f(self.g(self.lazy[r], self.tree[r]), s)
            if r & -r == r: break
        return 0

    def propagate_lazy(self, i):
        """
        lazy の値をトップダウンで更新する　（ O(logN) ）
        """
        for k in range(i.bit_length()-1,0,-1):
            x = i>>k
            if self.lazy[x] == self.eh:
                continue
            laz = self.lazy[x]
            self.lazy[(x<<1)|1] = self.h(laz, self.lazy[(x<<1)|1])
            self.lazy[x<<1] = self.h(laz, self.lazy[x<<1])
            self.tree[x] = self.g(laz, self.tree[x])   
            self.lazy[x] = self.eh


    def propagate_tree(self, i):
        """
        tree の値をボトムアップで更新する　（ O(logN) ）
        """
        while i>1:
            i>>=1
            self.tree[i] = self.f(self.g(self.lazy[i<<1], self.tree[i<<1]), self.g(self.lazy[(i<<1)|1], self.tree[(i<<1)|1]))

    def __getitem__(self, i):
        return self.get(i)

    def __iter__(self):
        for x in range(1, self.size):
            if self.lazy[x] == self.eh:
                continue
            self.lazy[(x<<1)|1] = self.h(self.lazy[x], self.lazy[(x<<1)|1])
            self.lazy[x<<1] = self.h(self.lazy[x], self.lazy[x<<1])
            self.tree[x] = self.g(self.lazy[x], self.tree[x])
            self.lazy[x] = self.eh
        for xh, x in zip(self.lazy[self.size:self.size+self.n], self.tree[self.size:self.size+self.n]):
            yield self.g(xh,x)

    def __str__(self):
        return str(list(self))



from itertools import accumulate
import sys
input = sys.stdin.readline

MOD = 998244353
off = 1<<22

N, Q = map(int, input().split())

P = [pow(10,p,MOD) for p in range(N+1)]
SP = [0]
for p in P:
    SP.append((SP[-1]+p)%MOD)

ef = 0
def f(x, y):
    x0, x1 = divmod(x,off)
    y0, y1 = divmod(y,off)
    res = x0*P[y1]+y0
    res %= MOD
    return (res*off) + x1+y1

eh = -1
def h(a,b):
    return a if a != eh else b

def g(a, x):
    x1 = x%off
    res = a*SP[x1]%MOD
    return (res*off) + x1

st = LazySegmentTree(N, f, g, h, ef, eh)

st.built([(off) + 1]*N)
res = [""]*Q
for i in range(Q):
    L, R, D = map(int, input().split())
    st.update_range(L-1, R, D)
    res[i] = str((st.get_range(0,N)//off)%MOD)
print("\n".join(res))

Solution (Python):
class LazySegmentTree():
    def __init__(self, array, f, g, h, ti, ei):
        self.f = f
        self.g = g
        self.h = h
        self.ti = ti
        self.ei = ei
        self.height = height = len(array).bit_length()
        self.n = n = 2**height
        self.dat = dat = [ti] * n + array + [ti] * (n - len(array))
        self.laz = [ei] * (2 * n)
        for i in range(n - 1, 0, -1):  
            dat[i] = f(dat[i << 1], dat[i << 1 | 1])
 
    def reflect(self, k):
        
        dat = self.dat
        ei = self.ei
        laz = self.laz
        g = self.g
        return self.dat[k] if laz[k] is ei else g(dat[k], laz[k])
 
    def evaluate(self, k):
        
        laz = self.laz
        ei = self.ei
        reflect = self.reflect
        dat = self.dat
        h = self.h
        if laz[k] is ei:
            return
        laz[(k << 1) | 0] = h(laz[(k << 1) | 0], laz[k])
        laz[(k << 1) | 1] = h(laz[(k << 1) | 1], laz[k])
        dat[k] = reflect(k)
        laz[k] = ei
 
    def thrust(self, k):
        height = self.height
        evaluate = self.evaluate
        for i in range(height, 0, -1):
            evaluate(k >> i)
 
    def recalc(self, k):
        dat = self.dat
        reflect = self.reflect
        f = self.f
        while k:
            k >>= 1
            dat[k] = f(reflect((k << 1) | 0), reflect((k << 1) | 1))
 
    def update(self, a, b, x):
        
        thrust = self.thrust
        n = self.n
        h = self.h
        laz = self.laz
        recalc = self.recalc
        a += n
        b += n - 1
        l = a
        r = b + 1
        thrust(a)
        thrust(b)
        while l < r:
            if l & 1:
                laz[l] = h(laz[l], x)
                l += 1
            if r & 1:
                r -= 1
                laz[r] = h(laz[r], x)
            l >>= 1
            r >>= 1
        recalc(a)
        recalc(b)
 
    def set_val(self, a, x):
        
        n = self.n
        thrust = self.thrust
        dat = self.dat
        laz = self.laz
        recalc = self.recalc
        ei = self.ei
        a += n
        thrust(a)
        dat[a] = x
        laz[a] = ei
        recalc(a)
 
    def query(self, a, b):
        
        f = self.f
        ti = self.ti
        n = self.n
        thrust = self.thrust
        reflect = self.reflect
        a += n
        b += n - 1
        thrust(a)
        thrust(b)
        l = a
        r = b + 1
        vl = vr = ti
        while l < r:
            if l & 1:
                vl = f(vl, reflect(l))
                l += 1
            if r & 1:
                r -= 1
                vr = f(reflect(r), vr)
            l >>= 1
            r >>= 1
        return f(vl, vr)
    
def pow_k(x,n,p=10**9+7):
    if n==0:
        return 1
    K=1
    while n>1:
        if n%2!=0:
            K=(K*x)%p
        x=(x*x)%p
        n//=2
    return (K*x)%p

mod=998244353
def f(a, b):
    an,ah=a
    bn,bh=b
    return ((an*tenmod[bh]+bn)%mod,ah+bh)
 
def g(a, b):
    an,ah=a
    return (((tenmod[ah]-1)*443664157)%mod*b,ah)

h = lambda a, b: b
ti = (0,0)
ei = 0

import sys
input = sys.stdin.readline
MI=lambda:map(int,input().split())
N,Q=MI()

tenmod=[pow_k(10,i,mod) for i in range(N+1)]
lst=LazySegmentTree([(1,1)]*N,f=f,g=g,h=h,ti=ti,ei=ei)


for _ in [0]*Q:
    l,r,d=MI()
    lst.update(l-1,r,d)
    print(lst.query(0,N)[0])

Solution (Python):
class LazySegmentTree():
    def __init__(self, array, f, g, h, ti, ei):
        self.f = f
        self.g = g
        self.h = h
        self.ti = ti
        self.ei = ei
        self.height = height = len(array).bit_length()
        self.n = n = 2**height
        self.dat = dat = [ti] * n + array + [ti] * (n - len(array))
        self.laz = [ei] * (2 * n)
        for i in range(n - 1, 0, -1):  
            dat[i] = f(dat[i << 1], dat[i << 1 | 1])
 
    def reflect(self, k):
        
        dat = self.dat
        ei = self.ei
        laz = self.laz
        g = self.g
        return self.dat[k] if laz[k] is ei else g(dat[k], laz[k])
 
    def evaluate(self, k):
        
        laz = self.laz
        ei = self.ei
        reflect = self.reflect
        dat = self.dat
        h = self.h
        if laz[k] is ei:
            return
        laz[(k << 1) | 0] = h(laz[(k << 1) | 0], laz[k])
        laz[(k << 1) | 1] = h(laz[(k << 1) | 1], laz[k])
        dat[k] = reflect(k)
        laz[k] = ei
 
    def thrust(self, k):
        height = self.height
        evaluate = self.evaluate
        for i in range(height, 0, -1):
            evaluate(k >> i)
 
    def recalc(self, k):
        dat = self.dat
        reflect = self.reflect
        f = self.f
        while k:
            k >>= 1
            dat[k] = f(reflect((k << 1) | 0), reflect((k << 1) | 1))
 
    def update(self, a, b, x):
        
        thrust = self.thrust
        n = self.n
        h = self.h
        laz = self.laz
        recalc = self.recalc
        a += n
        b += n - 1
        l = a
        r = b + 1
        thrust(a)
        thrust(b)
        while l < r:
            if l & 1:
                laz[l] = h(laz[l], x)
                l += 1
            if r & 1:
                r -= 1
                laz[r] = h(laz[r], x)
            l >>= 1
            r >>= 1
        recalc(a)
        recalc(b)
 
    def set_val(self, a, x):
        
        n = self.n
        thrust = self.thrust
        dat = self.dat
        laz = self.laz
        recalc = self.recalc
        ei = self.ei
        a += n
        thrust(a)
        dat[a] = x
        laz[a] = ei
        recalc(a)
 
    def query(self, a, b):
        
        f = self.f
        ti = self.ti
        n = self.n
        thrust = self.thrust
        reflect = self.reflect
        a += n
        b += n - 1
        thrust(a)
        thrust(b)
        l = a
        r = b + 1
        vl = vr = ti
        while l < r:
            if l & 1:
                vl = f(vl, reflect(l))
                l += 1
            if r & 1:
                r -= 1
                vr = f(reflect(r), vr)
            l >>= 1
            r >>= 1
        return f(vl, vr)
    
def pow_k(x,n,p=10**9+7):
    if n==0:
        return 1
    K=1
    while n>1:
        if n%2!=0:
            K=(K*x)%p
        x=(x*x)%p
        n//=2
    return (K*x)%p


import sys
input = sys.stdin.readline
MI=lambda:map(int,input().split())
N,Q=MI()
H=10**9+7

mod=998244353
tenmod=[pow_k(10,i,mod) for i in range(N+1)]

inv9=pow_k(9,mod-2,mod)
def f(a, b):
    an,ah=divmod(a,H)
    bn,bh=divmod(b,H)
    return ((an*tenmod[bh]+bn)%mod)*H + ah+bh
 
def g(a, b):
    ah=a%H
    return (((tenmod[ah]-1)*inv9)%mod*b)*H + ah

h = lambda a, b: b
ti = 0
ei = 0


lst=LazySegmentTree([1*H+1]*N,f=f,g=g,h=h,ti=ti,ei=ei)

for _ in [0]*Q:
    l,r,d=MI()
    lst.update(l-1,r,d)
    print(lst.query(0,N)//H)

Solution (Python):
class LazySegmentTree:

    __slots__ = ["n", "data", "lazy", "me", "oe", "fmm", "fmo", "foo"]

    def __init__(self, monoid_data, monoid_identity, operator_identity, func_monoid_monoid, func_monoid_operator, func_operator_operator):
        self.me = monoid_identity
        self.oe = operator_identity
        self.fmm = func_monoid_monoid
        self.fmo = func_monoid_operator
        self.foo = func_operator_operator

        self.n = len(monoid_data)
        self.data = monoid_data * 2
        for i in range(self.n-1, 0, -1):
            self.data[i] = self.fmm(self.data[2*i], self.data[2*i+1])
        self.lazy = [self.oe] * (self.n * 2)
        

    def replace(self, index, value):
        index += self.n

        
        for shift in range(index.bit_length()-1, 0, -1):
            i = index >> shift
            self.lazy[2*i]   = self.foo(self.lazy[2*i],   self.lazy[i])
            self.lazy[2*i+1] = self.foo(self.lazy[2*i+1], self.lazy[i])
            self.data[i] = self.fmo(self.data[i], self.lazy[i])
            self.lazy[i] = self.oe

        
        self.data[index] = value
        self.lazy[index] = self.oe

        
        i = index
        while i > 1:
            i //= 2
            self.data[i] = self.fmm( self.fmo(self.data[2*i], self.lazy[2*i]), self.fmo(self.data[2*i+1], self.lazy[2*i+1]) )
            self.lazy[i] = self.oe


    def effect(self, l, r, operator):
        l += self.n
        r += self.n
        
        
        indices = []
        l0 = (l // (l & -l))     // 2
        r0 = (r // (r & -r) - 1) // 2
        while r0 > l0:
            indices.append(r0)
            r0 //= 2
        while l0 > r0:
            indices.append(l0)
            l0 //= 2
        while l0 and l0 != r0:
            indices.append(r0)
            r0 //= 2
            if l0 == r0:
                break
            indices.append(l0)
            l0 //= 2
        while r0:
            indices.append(r0)
            r0 //= 2

        
        for i in reversed(indices):
            self.lazy[2*i]   = self.foo(self.lazy[2*i],   self.lazy[i])
            self.lazy[2*i+1] = self.foo(self.lazy[2*i+1], self.lazy[i])
            self.data[i] = self.fmo(self.data[i], self.lazy[i])
            self.lazy[i] = self.oe

        
        while l < r:
            if l % 2:
                self.lazy[l] = self.foo(self.lazy[l], operator)
                l += 1
            if r % 2:
                r -= 1
                self.lazy[r] = self.foo(self.lazy[r], operator)
            l //= 2
            r //= 2

        
        for i in indices:
            self.data[i] = self.fmm( self.fmo(self.data[2*i], self.lazy[2*i]), self.fmo(self.data[2*i+1], self.lazy[2*i+1]) )
            self.lazy[i] = self.oe
            
        
    def folded(self, l, r):
        l += self.n
        r += self.n

        
        indices = []
        l0 = (l // (l & -l))     // 2
        r0 = (r // (r & -r) - 1) // 2
        while r0 > l0:
            indices.append(r0)
            r0 //= 2
        while l0 > r0:
            indices.append(l0)
            l0 //= 2
        while l0 and l0 != r0:
            indices.append(r0)
            r0 //= 2
            if l0 == r0:
                break
            indices.append(l0)
            l0 //= 2
        while r0:
            indices.append(r0)
            r0 //= 2
        
        
        for i in reversed(indices):
            self.lazy[2*i]   = self.foo(self.lazy[2*i],   self.lazy[i])
            self.lazy[2*i+1] = self.foo(self.lazy[2*i+1], self.lazy[i])
            self.data[i] = self.fmo(self.data[i], self.lazy[i])
            self.lazy[i] = self.oe

        
        left_folded = self.me
        right_folded = self.me
        while l < r:
            if l % 2:
                left_folded = self.fmm(left_folded, self.fmo(self.data[l], self.lazy[l]))
                l += 1
            if r % 2:
                r -= 1
                right_folded = self.fmm(self.fmo(self.data[r], self.lazy[r]), right_folded)
            l //= 2
            r //= 2
        return self.fmm(left_folded, right_folded)

N,Q=map(int,input().split())
l,r,d=0,0,0
mod=998244353
P=[1]*(10**6+1)
for i in range(10**6):
  P[i+1]=P[i]*10%mod
inv9=pow(9,mod-2,mod)
def f(x,y):
  if x==(0,0):
    return y
  if y==(0,0):
    return x
  return ((x[0]*P[y[1]]+y[0])%mod,x[1]+y[1])

def g(x,y):
  if y!=-1:
    return ((P[x[1]]-1)*y*inv9%mod,x[1])
  else:
    return x

def h(x,y):
  if y==-1 and x!=-1:
    return x
  return y

n=1
while n<N:
  n<<=1
Y=n-N
X=LazySegmentTree([(0,1) if i<Y else (1,1) for i in range(n)],(0,0),-1,f,g,h)
for i in range(Q):
  l,r,d=map(int,input().split())
  l+=Y-1
  r+=Y
  X.effect(l,r,d)
  print(X.folded(0,n)[0])