Submission #636747

#	Time	Username	Problem	Language	Result	Execution time	Memory
636747		imeimi2000	Mutating DNA (IOI21_dna)	C++17	100 / 100	41 ms	7364 KiB

dna

#include "dna.h"
#include <cstring>
#include <algorithm>

using namespace std;

int n;
int cnt[100005][3][3];
void init(string a, string b) {
	n = a.size();
	int C[256];
	C['A'] = 0;
	C['C'] = 1;
	C['T'] = 2;
	for (int i = 1; i <= n; ++i) {
		memcpy(cnt[i], cnt[i - 1], sizeof(cnt[i]));
		++cnt[i][C[a[i - 1]]][C[b[i - 1]]];
	}
}

int get_distance(int x, int y) {
	int D[3][3];
	memcpy(D, cnt[y + 1], sizeof(D));
	for (int i = 0; i < 3; ++i) for (int j = 0; j < 3; ++j) D[i][j] -= cnt[x][i][j];
	int ans = 0;
	for (int i = 0; i < 3; ++i) {
		for (int j = i + 1; j < 3; ++j) {
			int v = min(D[i][j], D[j][i]);
			ans += v;
			D[i][j] -= v;
			D[j][i] -= v;
		}
	}
	int v = min({ D[0][1], D[1][2], D[2][0] });
	D[0][1] -= v;
	D[1][2] -= v;
	D[2][0] -= v;
	ans += v + v;
	v = min({ D[1][0], D[2][1], D[0][2] });
	D[1][0] -= v;
	D[2][1] -= v;
	D[0][2] -= v;
	ans += v + v;
	for (int i = 0; i < 3; ++i) for (int j = 0; j < 3; ++j) if (i != j && D[i][j]) return -1;
	return ans;
}

Compilation message (stderr)

dna.cpp: In function 'void init(std::string, std::string)':
dna.cpp:17:22: warning: array subscript has type 'char' [-Wchar-subscripts]
   17 |   ++cnt[i][C[a[i - 1]]][C[b[i - 1]]];
      |                      ^
dna.cpp:17:35: warning: array subscript has type 'char' [-Wchar-subscripts]
   17 |   ++cnt[i][C[a[i - 1]]][C[b[i - 1]]];
      |                                   ^

• Subtask 1: 21 / 21
• Subtask 2: 22 / 22
• Subtask 3: 13 / 13
• Subtask 4: 28 / 28
• Subtask 5: 16 / 16