Submission #204071

#	Time	Username	Problem	Language	Result	Execution time	Memory
204071		ics0503	Lamps (JOI19_lamps)	C++17	100 / 100	68 ms	16120 KiB

lamp

#include<stdio.h>
int D[1212121][3];
char a[1212121], b[1212121];
int min(int a, int b) { if (a < b)return a; return b; }
int get(char a, int tp) {
	if (tp == 0)return '0';
	if (tp == 1)return '1';
	return a;
}
int main() {
	int n; scanf("%d%s%s", &n, a + 1, b + 1);
	int i, j, k;
	D[0][0] = D[0][1] = 1e9; D[0][2] = 0;
	for (i = 1; i <= n; i++) {
		for (j = 0; j < 3; j++) {
			D[i][j] = 1e9;
			for (k = 0; k < 3; k++) {
				D[i][j] = min(D[i][j], D[i - 1][k] 
					+ (j != 2 && j != k)
					+ ((i==1 || get(a[i - 1], k) == b[i - 1]) && get(a[i], j) != b[i]));
			}
		}
	}
	int ans = 1e9;
	for (i = 0; i < 3; i++)ans = min(ans, D[n][i]);
	printf("%d", ans);
	return 0;
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:11:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n; scanf("%d%s%s", &n, a + 1, b + 1);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 4 / 4
• Subtask 4: 49 / 49