#include <bits/stdc++.h>
using namespace std;
const int N = (int)1e6 + 7;
string a, b;
int n;
int dp[N][3][2];
/*
dp[pos][operation][xor]
operation
0 = off
1 = on
2 = do not touch
*/
main() {
memset(dp, 63, sizeof dp);
scanf("%d", &n);
cin >> a >> b;
a = " " + a;
b = " " + b;
dp[0][2][0] = 0;
for (int i = 1; i <= n; i++) {
for (int j = 0; j < 3; j++) {
if (b[i] - '0' == j) {
dp[i][j][0] = min(dp[i][j][0], dp[i - 1][j][0]);
dp[i][j][0] = min(dp[i][j][0], dp[i - 1][j][1]);
for (int l = 0; l < 3; l++) {
dp[i][j][0] = min(dp[i][j][0], dp[i - 1][l][0] + 1);
dp[i][j][0] = min(dp[i][j][0], dp[i - 1][l][1] + 1);
}
}
if (b[i] - '0' == (j ^ 1)) {
dp[i][j][1] = min(dp[i][j][1], dp[i - 1][j][1]);
dp[i][j][1] = min(dp[i][j][1], dp[i - 1][j][0] + 1);
for (int l = 0; l < 3; l++) {
dp[i][j][1] = min(dp[i][j][1], dp[i - 1][l][1] + 1);
}
}
if (j == 2 && b[i] == a[i]) {
for (int l = 0; l < 3; l++) {
dp[i][j][0] = min(dp[i][j][0], dp[i - 1][l][0] + 1);
dp[i][j][0] = min(dp[i][j][0], dp[i - 1][l][1] + 1);
}
}
if (j == 2 && b[i] != a[i]) {
for (int l = 0; l < 3; l++) {
dp[i][j][1] = min(dp[i][j][1], dp[i - 1][l][0] + 1);
dp[i][j][1] = min(dp[i][j][1], dp[i - 1][l][1]);
}
}
}
}
int ans = dp[0][1][0];
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 2; j++) {
ans = min(ans, dp[n][i][j]);
}
}
printf("%d\n", ans);
}
Compilation message
lamp.cpp:18:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
main() {
^
lamp.cpp: In function 'int main()':
lamp.cpp:20:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", &n);
~~~~~^~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
22 ms |
23808 KB |
Output is correct |
2 |
Incorrect |
22 ms |
23808 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
22 ms |
23808 KB |
Output is correct |
2 |
Incorrect |
22 ms |
23808 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
26 ms |
23928 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
22 ms |
23808 KB |
Output is correct |
2 |
Incorrect |
22 ms |
23808 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |