扩展欧几里得

def solve(____):
    def extended_gcd(____):
        if b == ____:
            return a, ____, ____
        gcd, x1, y1 = extended_gcd(____)
        x = y1
        y = x1 - (____) * y1
        return gcd, x, y
    gcd, x, y = extended_gcd(int(____), int(____))
    print(____)