Submission #704725

#	Time	Username	Problem	Language	Result	Execution time	Memory
704725		rainboy	스탬프 수집 (JOI16_ho_t2)	C11	100 / 100	6 ms	6740 KiB

2016_ho_t2

#include <stdio.h>
#include <string.h>

#define N	100000

long long max(long long a, long long b) { return a > b ? a : b; }

int main() {
	static char cc[N + 1];
	static long long dp[N + 1][4], dq[N + 1][4];
	int n, i, a;
	long long ans;

	scanf("%d%s", &n, cc);
	dp[0][0] = 1;
	for (i = 0; i < n; i++) {
		memcpy(dp[i + 1], dp[i], sizeof dp[i]);
		if (cc[i] == 'J')
			dp[i + 1][1] += dp[i + 1][0];
		else if (cc[i] == 'O')
			dp[i + 1][2] += dp[i + 1][1];
		else
			dp[i + 1][3] += dp[i + 1][2];
	}
	dq[n][3] = 1;
	for (i = n - 1; i >= 0; i--) {
		memcpy(dq[i], dq[i + 1], sizeof dq[i + 1]);
		if (cc[i] == 'J')
			dq[i][0] += dq[i][1];
		else if (cc[i] == 'O')
			dq[i][1] += dq[i][2];
		else
			dq[i][2] += dq[i][3];
	}
	ans = 0;
	for (i = 0; i <= n; i++)
		for (a = 0; a < 3; a++)
			ans = max(ans, dp[n][3] + dp[i][a] * dq[i][a + 1]);
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

2016_ho_t2.c: In function 'main':
2016_ho_t2.c:14:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |  scanf("%d%s", &n, cc);
      |  ^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 30 / 30
• Subtask 2: 20 / 20
• Subtask 3: 50 / 50