Buggy python submission (verdict: Time Limit Exceeded):
def main():
    """"ここに今までのコード"""
    import sys
    read = sys.stdin.buffer.read
    readline = sys.stdin.buffer.readline
    readlines = sys.stdin.buffer.readlines

    n = int(readline())
    data = tuple(map(int,read().split()))
    m1 = data[0]
    ab = data[1:1+2*m1]
    m2 = data[1+2*m1]
    cd = data[2+2*m1:2+2*(m1+m2)]
    m3 = data[2+2*(m1+m2)]
    ef = data[3+2*(m1+m2):]

    mod = 998244353
    mods = [1] * (n+10)
    base = pow(10,18,mod)
    for i in range(1,n+1):
        mods[i] = (mods[i-1] * base)%mod

    def calc_node(xy):
        links = [[] for _ in range(n+1)]
        it = iter(xy)
        for x,y in zip(it,it):
            if(x < y):
                x,y = y,x
            links[y].append(x)

        group = [-1] * (n+1)
        group[-1] = 0
        num_max = 1
        for i in range(n,0,-1):
            remain = set(range(num_max+2))
            for j in links[i]:
                remain.discard(group[j])
            num = min(remain)
            group[i] = num
            num_max = max(num_max,num)

        res = [0] * (num_max+1)
        for i,num in enumerate(group[1:],1):
            res[num] += mods[i]
            res[num] %= mod

        return res

    x = calc_node(ab)
    y = calc_node(cd)
    z = calc_node(ef)

    if(len(x) < len(y)):
        x,y = y,x
    if(len(y) < len(z)):
        y,z = z,y
    if(len(x) < len(y)):
        x,y = y,x


    len_2 = 2**(len(y)-1).bit_length()
    yz = [0] * (len_2)
    for j in range(len(y)):
        for k in range(len(z)):
            yz[j^k] += y[j]*z[k]
            yz[j^k] %= mod

    ans = 0
    for i,j in zip(x,yz):
        ans += i*j
        ans %= mod

    print(ans)

if __name__ == '__main__':
    main()

Fixed submission:
def main():
    """"ここに今までのコード"""
    import sys
    read = sys.stdin.buffer.read
    readline = sys.stdin.buffer.readline
    readlines = sys.stdin.buffer.readlines

    n = int(readline())
    data = tuple(map(int,read().split()))
    m1 = data[0]
    ab = data[1:1+2*m1]
    m2 = data[1+2*m1]
    cd = data[2+2*m1:2+2*(m1+m2)]
    m3 = data[2+2*(m1+m2)]
    ef = data[3+2*(m1+m2):]

    mod = 998244353
    mods = [1] * (n+10)
    base = pow(10,18,mod)
    for i in range(1,n+1):
        mods[i] = (mods[i-1] * base)%mod

    def calc_node(xy):
        links = [[] for _ in range(n+1)]
        it = iter(xy)
        for x,y in zip(it,it):
            if(x < y):
                x,y = y,x
            links[y].append(x)

        group = [-1] * (n+1)
        g_bit = [0] * (n+1)
        group[-1] = 0
        g_bit[-1] = 1
        num_max = 1
        for i in range(n,0,-1):
            tmp = 0
            for j in links[i]:
                tmp |= g_bit[j]
            cnt = 0
            while(tmp&1):
                tmp = tmp>>1
                cnt+=1
            group[i] = cnt
            g_bit[i] = 1 << cnt
            num_max = max(num_max,cnt)

        res = [0] * (num_max+1)
        for i,num in enumerate(group[1:],1):
            res[num] += mods[i]
            res[num] %= mod

        return res

    x = calc_node(ab)
    y = calc_node(cd)
    z = calc_node(ef)

    if(len(x) < len(y)):
        x,y = y,x
    if(len(y) < len(z)):
        y,z = z,y
    if(len(x) < len(y)):
        x,y = y,x


    len_2 = 2**(len(y)-1).bit_length()
    yz = [0] * (len_2)
    for j in range(len(y)):
        for k in range(len(z)):
            yz[j^k] += y[j]*z[k]
            yz[j^k] %= mod

    ans = 0
    for i,j in zip(x,yz):
        ans += i*j
        ans %= mod

    print(ans)

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

n = int(readline())
data = tuple(map(int,read().split()))
m1 = data[0]
ab = data[1:1+2*m1]
m2 = data[1+2*m1]
cd = data[2+2*m1:2+2*(m1+m2)]
m3 = data[2+2*(m1+m2)]
ef = data[3+2*(m1+m2):]

mod = 998244353
mods = [1] * (n+10)
base = pow(10,18,mod)
for i in range(1,n+1):
    mods[i] = (mods[i-1] * base)%mod

def calc_node(xy):
    links = [[] for _ in range(n+1)]
    it = iter(xy)
    for x,y in zip(it,it):
        links[x].append(y)
        links[y].append(x)

    group = [-1] * (n+1)
    group[-1] = 0
    num_max = 1
    for i in range(n,0,-1):
        remain = set(range(num_max+2))
        for j in links[i]:
            if(i < j):
                remain.discard(group[j])
        num = min(remain)
        group[i] = num
        num_max = max(num_max,num)

    res = [0] * (num_max+1)
    for i,num in enumerate(group[1:],1):
        res[num] += mods[i]
        res[num] %= mod

    return res

x = calc_node(ab)
y = calc_node(cd)
z = calc_node(ef)


if(len(x) < len(y)):
    x,y = y,x
if(len(y) < len(z)):
    y,z = z,y
if(len(x) < len(y)):
    x,y = y,x


len_2 = 2**(len(y)-1).bit_length()
yz = [0] * (len_2)
for j in range(len(y)):
    for k in range(len(z)):
        yz[j^k] += y[j]*z[k]
        yz[j^k] %= mod

ans = 0
for i,j in zip(x,yz):
    ans += i*j
    ans %= mod

print(ans)

Fixed submission:
def main():
    """"ここに今までのコード"""
    import sys
    read = sys.stdin.buffer.read
    readline = sys.stdin.buffer.readline
    readlines = sys.stdin.buffer.readlines

    n = int(readline())
    data = tuple(map(int,read().split()))
    m1 = data[0]
    ab = data[1:1+2*m1]
    m2 = data[1+2*m1]
    cd = data[2+2*m1:2+2*(m1+m2)]
    m3 = data[2+2*(m1+m2)]
    ef = data[3+2*(m1+m2):]

    mod = 998244353
    mods = [1] * (n+10)
    base = pow(10,18,mod)
    for i in range(1,n+1):
        mods[i] = (mods[i-1] * base)%mod

    def calc_node(xy):
        links = [[] for _ in range(n+1)]
        it = iter(xy)
        for x,y in zip(it,it):
            if(x < y):
                x,y = y,x
            links[y].append(x)

        group = [-1] * (n+1)
        g_bit = [0] * (n+1)
        group[-1] = 0
        g_bit[-1] = 1
        num_max = 1
        for i in range(n,0,-1):
            tmp = 0
            for j in links[i]:
                tmp |= g_bit[j]
            cnt = 0
            while(tmp&1):
                tmp = tmp>>1
                cnt+=1
            group[i] = cnt
            g_bit[i] = 1 << cnt
            num_max = max(num_max,cnt)

        res = [0] * (num_max+1)
        for i,num in enumerate(group[1:],1):
            res[num] += mods[i]
            res[num] %= mod

        return res

    x = calc_node(ab)
    y = calc_node(cd)
    z = calc_node(ef)

    if(len(x) < len(y)):
        x,y = y,x
    if(len(y) < len(z)):
        y,z = z,y
    if(len(x) < len(y)):
        x,y = y,x


    len_2 = 2**(len(y)-1).bit_length()
    yz = [0] * (len_2)
    for j in range(len(y)):
        for k in range(len(z)):
            yz[j^k] += y[j]*z[k]
            yz[j^k] %= mod

    ans = 0
    for i,j in zip(x,yz):
        ans += i*j
        ans %= mod

    print(ans)

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

n = int(readline())
data = tuple(map(int,read().split()))
m1 = data[0]
ab = data[1:1+2*m1]
m2 = data[1+2*m1]
cd = data[2+2*m1:2+2*(m1+m2)]
m3 = data[2+2*(m1+m2)]
ef = data[3+2*(m1+m2):]

mod = 998244353
mods = [1] * (n+10)
base = pow(10,18,mod)
for i in range(1,n+1):
    mods[i] = (mods[i-1] * base)%mod

def calc_node(xy):
    links = [[] for _ in range(n+1)]
    it = iter(xy)
    for x,y in zip(it,it):
        links[x].append(y)
        links[y].append(x)

    group = [-1] * (n+1)
    group[-1] = 0
    num_max = 1
    for i in range(n,0,-1):
        remain = set(range(num_max+2))
        for j in links[i]:
            if(i < j):
                remain.discard(group[j])
        num = min(remain)
        group[i] = num
        num_max = max(num_max,num)

    res = [0] * (num_max+1)
    for i,num in enumerate(group[1:],1):
        res[num] += mods[i]
        res[num] %= mod

    return res

x = calc_node(ab)
y = calc_node(cd)
z = calc_node(ef)


if(len(x) < len(y)):
    x,y = y,x
if(len(y) < len(z)):
    y,z = z,y
if(len(x) < len(y)):
    x,y = y,x


len_2 = 2**(len(y)-1).bit_length()
comb = [[] for _ in range(len_2)]
for j in range(len(y)):
    for k in range(len(z)):
        comb[j^k].append((j,k))

ans = 0
for i,x_tmp in enumerate(x):
    if(len(comb) == i):
        break

    yz = 0
    for j,k in comb[i]:
        yz += y[j]*z[k]
        yz %= mod
    ans += x_tmp * yz
    ans %= mod

print(ans)

Fixed submission:
def main():
    """"ここに今までのコード"""
    import sys
    read = sys.stdin.buffer.read
    readline = sys.stdin.buffer.readline
    readlines = sys.stdin.buffer.readlines

    n = int(readline())
    data = tuple(map(int,read().split()))
    m1 = data[0]
    ab = data[1:1+2*m1]
    m2 = data[1+2*m1]
    cd = data[2+2*m1:2+2*(m1+m2)]
    m3 = data[2+2*(m1+m2)]
    ef = data[3+2*(m1+m2):]

    mod = 998244353
    mods = [1] * (n+10)
    base = pow(10,18,mod)
    for i in range(1,n+1):
        mods[i] = (mods[i-1] * base)%mod

    def calc_node(xy):
        links = [[] for _ in range(n+1)]
        it = iter(xy)
        for x,y in zip(it,it):
            if(x < y):
                x,y = y,x
            links[y].append(x)

        group = [-1] * (n+1)
        g_bit = [0] * (n+1)
        group[-1] = 0
        g_bit[-1] = 1
        num_max = 1
        for i in range(n,0,-1):
            tmp = 0
            for j in links[i]:
                tmp |= g_bit[j]
            cnt = 0
            while(tmp&1):
                tmp = tmp>>1
                cnt+=1
            group[i] = cnt
            g_bit[i] = 1 << cnt
            num_max = max(num_max,cnt)

        res = [0] * (num_max+1)
        for i,num in enumerate(group[1:],1):
            res[num] += mods[i]
            res[num] %= mod

        return res

    x = calc_node(ab)
    y = calc_node(cd)
    z = calc_node(ef)

    if(len(x) < len(y)):
        x,y = y,x
    if(len(y) < len(z)):
        y,z = z,y
    if(len(x) < len(y)):
        x,y = y,x


    len_2 = 2**(len(y)-1).bit_length()
    yz = [0] * (len_2)
    for j in range(len(y)):
        for k in range(len(z)):
            yz[j^k] += y[j]*z[k]
            yz[j^k] %= mod

    ans = 0
    for i,j in zip(x,yz):
        ans += i*j
        ans %= mod

    print(ans)

if __name__ == '__main__':
    main()