Submission #522398

#	Time	Username	Problem	Language	Result	Execution time	Memory
522398		LucaDantas	Alternating Current (BOI18_alternating)	C++17	13 / 100	3058 ms	332 KiB

alternating

#include <bits/stdc++.h>
using namespace std;

constexpr int maxn = 20;

using pii = pair<int,int>;

int a[maxn], b[maxn];
bool mark[maxn][2];

int main() {
	int n, m; scanf("%d %d", &n, &m);
	for(int i = 0; i < m; i++)
		scanf("%d %d", &a[i], &b[i]);

	vector<int> ans(m);

	for(int mask = 0; mask < (1 << m); mask++) {
		memset(mark, 0, sizeof mark);

		for(int i = 0; i < m; i++) {
			int tp = (mask&(1<<i)) > 0;
			for(int j = a[i]; j != b[i]; j = j%n +1)
				mark[j][tp] = 1;
			mark[b[i]][tp] = 1;
		}

		bool ok = 1;
		for(int i = 1; i <= n; i++)
			if(!mark[i][0] || !mark[i][1]) ok = 0;

		if(ok) {
			for(int i = 0; i < m; i++)
				printf("%d", (mask&(1<<i)) > 0);
			puts("");

			return 0;
		}
	}

	puts("impossible");
}

Compilation message (stderr)

alternating.cpp: In function 'int main()':
alternating.cpp:12:17: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |  int n, m; scanf("%d %d", &n, &m);
      |            ~~~~~^~~~~~~~~~~~~~~~~
alternating.cpp:14:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |   scanf("%d %d", &a[i], &b[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 0 / 20
• Subtask 3: 0 / 22
• Subtask 4: 0 / 19
• Subtask 5: 0 / 26