Buggy python submission (verdict: Runtime Error):
import functools, fractions
 
def lcm(a, b):
    return a * b // fractions.gcd(a, b)
 
def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res
 
def check2(x, L, NM):
    return int((x-1)*NM/L)
 
 
def main():
    N,M = map(int,input().split())
    S = input()
    T = input()
    L = lcm(N,M)
    ans = L
 
 
    a = list(set(check(L, N)) & set(check(L, M)))
    for i in a:
        if S[check2(i, L, N)] != T[check2(i, L, M)]:
            ans = -1
            break
    print(ans)
if __main__ == '__main__':
  main()

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Buggy python submission (verdict: Runtime Error):
import functools, fractions
 
def lcm(a, b):
	return a * b // fractions.gcd(a, b)
 
def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res
 
def check2(x, L, NM):
    return int((x-1)*NM/L)
 
 
def main():
    N,M = map(int,input().split())
    S = input()
    T = input()
    L = lcm(N,M)
    ans = L
 
 
    a = list(set(check(L, N)) & set(check(L, M)))
    for i in a:
        if S[check2(i, L, N)] != T[check2(i, L, M)]:
            ans = -1
            break
    print(ans)
if __main__ == '__main__':
  main()

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Buggy python submission (verdict: Runtime Error):
import functools, fractions
 
def lcm(a, b):
	return a * b // fractions.gcd(a, b)
 
def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res
 
def check2(x, L, NM):
    return int((x-1)*NM/L)
 

def main():
 	N,M = map(int,input().split())
    S = input()
    T = input()
    L = lcm(N,M)
    ans = L


    a = list(set(check(L, N)) & set(check(L, M)))
    for i in a:
        if S[check2(i, L, N)] != T[check2(i, L, M)]:
            ans = -1
            break
    print(ans)
if __main__ == '__main__':
  main()

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Buggy python submission (verdict: Runtime Error):
import functools, fraction

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fraction.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Buggy python submission (verdict: Runtime Error):
import functools, math

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // math.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Buggy python submission (verdict: Runtime Error):
import functools, math

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // math.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Buggy python submission (verdict: Runtime Error):
import functools, math

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // math.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)

Fixed submission:
import functools, fractions

N,M = map(int,input().split())
S = input()
T = input()

def lcm(a, b):
	return a * b // fractions.gcd(a, b)

def check(L, NM):
    res = []
    for i in range(NM):
        res.append(int(i*(L/NM)+1))
    return res

def check2(x, L, NM):
    return int((x-1)*NM/L)

L = lcm(N,M)
ans = L


a = list(set(check(L, N)) & set(check(L, M)))
for i in a:
    if S[check2(i, L, N)] != T[check2(i, L, M)]:
        ans = -1
        break
print(ans)