Submission #164966

#	Time	Username	Problem	Language	Result	Execution time	Memory
164966		coloredrabbit	Ω (kriii4_P3)	C++17	Compilation error	0 ms	0 KiB

P3

#include <cstdio>
const ll MOD = 1e9+7;
using ll = long long;
ll _pow(ll a, int n) {
	if (n <= 1) return n % 2 ? a : 1;
	ll h = _pow(a, n >> 1);
	return ((h * h) % MOD) * (n % 2 ? a : 1) % MOD;
}
ll gcd(ll p, ll q) { return !q ? p : gcd(q, p % q); }
ll rev(ll x) { return _pow(x, MOD - 2); }
int main() {
	int P, Q, N, K;
	ll v, ans = 0, A, B, g, X;
	scanf("%d%d%d%d", &P, &Q, &N, &K);
	if (K == 0 || Q == P) puts("0");
	else if (K == N || Q == 0) puts("1");
	else {
		if(2*Q == P)
			ans = K * rev(N) % MOD;
		else {
			v = Q * rev(P - Q);
			ans = ((1 - _pow(v, K) + MOD) % MOD) * (rev(1 - _pow(v, N) + MOD) % MOD) % MOD;
		}
		printf("%lld", ans);
	}
	
	return 0;
}

Compilation message (stderr)

P3.cpp:2:7: error: 'll' does not name a type
 const ll MOD = 1e9+7;
       ^~
P3.cpp: In function 'll _pow(ll, int)':
P3.cpp:7:20: error: 'MOD' was not declared in this scope
  return ((h * h) % MOD) * (n % 2 ? a : 1) % MOD;
                    ^~~
P3.cpp: In function 'll rev(ll)':
P3.cpp:10:31: error: 'MOD' was not declared in this scope
 ll rev(ll x) { return _pow(x, MOD - 2); }
                               ^~~
P3.cpp: In function 'int main()':
P3.cpp:19:23: error: 'MOD' was not declared in this scope
    ans = K * rev(N) % MOD;
                       ^~~
P3.cpp:22:29: error: 'MOD' was not declared in this scope
    ans = ((1 - _pow(v, K) + MOD) % MOD) * (rev(1 - _pow(v, N) + MOD) % MOD) % MOD;
                             ^~~
P3.cpp:13:17: warning: unused variable 'A' [-Wunused-variable]
  ll v, ans = 0, A, B, g, X;
                 ^
P3.cpp:13:20: warning: unused variable 'B' [-Wunused-variable]
  ll v, ans = 0, A, B, g, X;
                    ^
P3.cpp:13:23: warning: unused variable 'g' [-Wunused-variable]
  ll v, ans = 0, A, B, g, X;
                       ^
P3.cpp:13:26: warning: unused variable 'X' [-Wunused-variable]
  ll v, ans = 0, A, B, g, X;
                          ^
P3.cpp:14:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%d", &P, &Q, &N, &K);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~