Buggy python submission (verdict: Time Limit Exceeded):
def main():
    n, a, b = map(int, input().split())
    mod = 10 ** 9 + 7 #素数
    
    def modpow(x, n, mod):
        res = 1
        while n:
            if n % 2:
                res *= x % mod
            x *= x % mod
            n >>= 1
        return res
    
    def cmb(n, r, mod):
        # 分子(n*(n-1)*...*(n-r+1))
        nume = 1
        for i in range(n-r+1, n+1):
            nume = nume * i# % mod
        # 分母（1*2*...*r）
        deno = 1
        for j in range(1, r+1):
            deno = deno * j % mod
        d = modpow(deno, mod-2, mod)
        return nume * d % mod
    
    all_cmb = pow(2, n, mod) - 1
    bad_a = cmb(n, a, mod)
    bad_b = cmb(n, b, mod)    
    print((all_cmb-bad_a-bad_b) % mod)

if __name__ == '__main__':
    main()



Fixed submission:
def main():
    n, a, b = map(int, input().split())
    mod = 10 ** 9 + 7 #素数
    
    def modpow(x, n, mod):
        res = 1
        while n:
            if n % 2:
                res *= x % mod
            x *= x % mod
            n >>= 1
        return res
    
    def cmb(n, r):
        # 分子(n*(n-1)*...*(n-r+1))
        nume = 1
        for i in range(n-r+1, n+1):
            nume = nume * i % mod
        # 分母（1*2*...*r）
        deno = 1
        for j in range(1, r+1):
            deno = deno * j % mod
        d = modpow(deno, mod-2, mod)
        return nume * d
    
    all_cmb = pow(2, n, mod) - 1
    bad_a = cmb(n, a)
    bad_b = cmb(n, b)    
    print((all_cmb-bad_a-bad_b) % mod)

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Runtime Error):
def main():
    n, a, b = map(int, input().split())
    mod = 10 ** 9 + 7 #素数
    
    def modpow(x, n, mod):
        res = 1
        while n:
            if n % 2:
                res *= x % mod
            x *= x % mod
            n >>= 1
        return res
    
    def cmb(n, r, mod):
        # 分子(n*(n-1)*...*(n-r+1))
        nume = 1
        for i in range(n-r+1, n+1):
            nume = nume * i
        # 分母（1*2*...*r）
        deno = 1
        for j in range(1, r+1):
            deno = deno * jc # % mod
        d = modpow(deno, mod-2, mod)
        return nume * d# % mod
    
    all_cmb = pow(2, n, mod) - 1
    bad_a = cmb(n, a, mod)
    bad_b = cmb(n, b, mod)    
    print((all_cmb-bad_a-bad_b) % mod)

if __name__ == '__main__':
    main()



Fixed submission:
def main():
    n, a, b = map(int, input().split())
    mod = 10 ** 9 + 7 #素数
    
    def modpow(x, n, mod):
        res = 1
        while n:
            if n % 2:
                res *= x % mod
            x *= x % mod
            n >>= 1
        return res
    
    def cmb(n, r):
        # 分子(n*(n-1)*...*(n-r+1))
        nume = 1
        for i in range(n-r+1, n+1):
            nume = nume * i % mod
        # 分母（1*2*...*r）
        deno = 1
        for j in range(1, r+1):
            deno = deno * j % mod
        d = modpow(deno, mod-2, mod)
        return nume * d
    
    all_cmb = pow(2, n, mod) - 1
    bad_a = cmb(n, a)
    bad_b = cmb(n, b)    
    print((all_cmb-bad_a-bad_b) % mod)

if __name__ == '__main__':
    main()

Buggy python submission (verdict: Runtime Error):
def main():
    n, a, b = map(int, input().split())
    mod = 10 ** 9 + 7 #素数
    
    def modpow(x, n, mod):
        res = 1
        while n:
            if n % 2:
                res *= x % mod
            x *= x % mod
            n >>= 1
        return res
    
    def cmb(n, r):
        # 分子(n*(n-1)*...*(n-r+1))
        nume = 1
        for i in range(n-r+1, n+1):
            nume = nume * i % mod
        # 分母（1*2*...*r）
        deno = 1
        for j in range(1, r+1):
            deno = deno * j % mod
        d = modpow(deno, mod-2, mod)
        return nume * d
    
    all_cmb = pow(2, n, mod) -　1
    bad_a = cmb(n, a)
    bad_b = cmb(n, b)    
    print((all_cmb-bad_a-bad_b) % mod)

if __name__ == '__main__':
    main()

Fixed submission:
def main():
    n, a, b = map(int, input().split())
    mod = 10 ** 9 + 7 #素数
    
    def modpow(x, n, mod):
        res = 1
        while n:
            if n % 2:
                res *= x % mod
            x *= x % mod
            n >>= 1
        return res
    
    def cmb(n, r):
        # 分子(n*(n-1)*...*(n-r+1))
        nume = 1
        for i in range(n-r+1, n+1):
            nume = nume * i % mod
        # 分母（1*2*...*r）
        deno = 1
        for j in range(1, r+1):
            deno = deno * j % mod
        d = modpow(deno, mod-2, mod)
        return nume * d
    
    all_cmb = pow(2, n, mod) - 1
    bad_a = cmb(n, a)
    bad_b = cmb(n, b)    
    print((all_cmb-bad_a-bad_b) % mod)

if __name__ == '__main__':
    main()