Submission #744626

# Submission time Handle Problem Language Result Execution time Memory
744626 2023-05-18T20:41:09 Z rainboy Round words (IZhO13_rowords) C
100 / 100
129 ms 46468 KB
/* https://codeforces.com/blog/entry/21372 */
/* https://arxiv.org/pdf/1208.0396.pdf */
/* https://oj.uz/submission/314177 */
#include <stdio.h>
#include <string.h>

#define N	2000
#define M	2000

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

int solve(char *aa, int n, char *bb, int m) {
	static int dp[N * 2 + 1][M + 1], dir[N * 2 + 1][M + 1];
	int l, i, j, x, ans;

	for (i = 0; i <= n * 2; i++)
		for (j = 0; j <= m; j++)
			if (i == 0 && j == 0)
				dp[i][j] = 0, dir[i][j] = -1;
			else {
				dp[i][j] = dir[i][j] = -1;
				if (j > 0 && dp[i][j] < (x = dp[i][j - 1]))
					dp[i][j] = x, dir[i][j] = 0;
				if (i > 0 && j > 0 && aa[(i - 1) % n] == bb[j - 1] && dp[i][j] < (x = dp[i - 1][j - 1] + 1))
					dp[i][j] = x, dir[i][j] = 1;
				if (i > 0 && dp[i][j] < (x = dp[i - 1][j]))
					dp[i][j] = x, dir[i][j] = 2;
			}
	ans = 0;
	for (l = 0; l < n; l++) {
		i = n + l, j = m, x = 0;
		while (dir[i][j] != -1)
			if (dir[i][j] == 0)
				j--;
			else if (dir[i][j] == 1)
				i--, j--, x++;
			else
				i--;
		ans = max(ans, x);
		i = l + 1, j = 0;
		dir[i][j] = -1;
		while (j < m)
			if (dir[i][j + 1] == 0)
				j++;
			else {
				dir[i][j + 1] = 0;
				if (i++ == n * 2)
					break;
				if (dir[i][j + 1] == 1)
					j++;
			}
	}
	return ans;
}

int main() {
	static char aa[N + 1], bb[M + 1];
	int n, m, i, j, ans, tmp;

	scanf("%s%s", aa, bb), n = strlen(aa), m = strlen(bb);
	ans = solve(aa, n, bb, m);
	for (i = 0, j = n - 1; i < j; i++, j--)
		tmp = aa[i], aa[i] = aa[j], aa[j] = tmp;
	ans = max(ans, solve(aa, n, bb, m));
	printf("%d\n", ans);
	return 0;
}

Compilation message

rowords.c: In function 'main':
rowords.c:60:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |  scanf("%s%s", aa, bb), n = strlen(aa), m = strlen(bb);
      |  ^~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 424 KB Output is correct
3 Correct 1 ms 596 KB Output is correct
4 Correct 1 ms 980 KB Output is correct
5 Correct 1 ms 980 KB Output is correct
6 Correct 17 ms 17820 KB Output is correct
7 Correct 40 ms 31624 KB Output is correct
8 Correct 93 ms 31632 KB Output is correct
9 Correct 97 ms 31624 KB Output is correct
10 Correct 86 ms 31748 KB Output is correct
11 Correct 73 ms 34764 KB Output is correct
12 Correct 67 ms 37836 KB Output is correct
13 Correct 116 ms 37796 KB Output is correct
14 Correct 105 ms 36008 KB Output is correct
15 Correct 102 ms 39020 KB Output is correct
16 Correct 107 ms 34072 KB Output is correct
17 Correct 78 ms 36428 KB Output is correct
18 Correct 120 ms 44764 KB Output is correct
19 Correct 70 ms 31632 KB Output is correct
20 Correct 129 ms 39964 KB Output is correct
21 Correct 75 ms 31480 KB Output is correct
22 Correct 103 ms 36232 KB Output is correct
23 Correct 95 ms 39116 KB Output is correct
24 Correct 103 ms 41200 KB Output is correct
25 Correct 127 ms 46468 KB Output is correct