Submission #707726

#	Time	Username	Problem	Language	Result	Execution time	Memory
707726		rainboy	JJOOII 2 (JOI20_ho_t2)	C11	100 / 100	5 ms	2504 KiB

ho_t2

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

#define N	200000
#define INF	0x3f3f3f3f

int min(int a, int b) { return a < b ? a : b; }

char *joi = "JOI";

int main() {
	static char cc[N + 1];
	static int qu[N], jj[N + 1], jj_[N + 1];
	int n, cnt, k, i, h, ans;

	scanf("%d%d%s", &n, &k, cc);
	for (i = 0; i <= n; i++)
		jj[i] = i;
	for (h = 2; h >= 0; h--) {
		cnt = 0;
		jj_[n] = -1;
		for (i = n - 1; i >= 0; i--) {
			if (cc[i] == joi[h])
				qu[cnt++] = i;
			jj_[i] = cnt >= k ? jj[qu[cnt - k] + 1] : -1;
		}
		memcpy(jj, jj_, (n + 1) * sizeof *jj_);
	}
	ans = INF;
	for (i = 0; i < n; i++)
		if (jj[i] != -1)
			ans = min(ans, jj[i] - i - k * 3);
	if (ans == INF)
		ans = -1;
	printf("%d\n", ans);
	return 0;
}

Compilation message (stderr)

ho_t2.c: In function 'main':
ho_t2.c:16:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |  scanf("%d%d%s", &n, &k, cc);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 1 / 1
• Subtask 2: 12 / 12
• Subtask 3: 87 / 87