我正在尝试进行hackerrank Matrix Rotation挑战。我的代码中有一个我无法找到的错误。该代码应该旋转测试矩阵的所有外环和内环r次数(1 <= r <= 10 E 9)。如果我没有对r执行模数,则代码运行正常,除了r的较高值值,它在hackerrank服务器上超时。如果我在r上执行模数,则代码将失败测试用例,其中r> =(r%number_of _elements_in_outer_loop)。我找不到这个bug。提前感谢您的回复。以下是代码(在Visual Studio 2015中进行测试)。对要求的黑客挑战是here
// MatrixRotation.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
// int i, j, k;
int m, n, r;
int rotations, rot;
int m_start, m_end, m_len;
int n_start, n_end, n_len;
int m_curr, n_curr;
//-------------------------------------------------------------------------
// For hackerrank testing
//-------------------------------------------------------------------------
int i, j;
for (i = 1; i <= 3; i++)
{
if (i == 1) std::cin >> m;
else if (i == 2) std::cin >> n;
else std::cin >> r;
}
int **matrix = new int*[m];
for (int i = 0; i < m; ++i) {
matrix[i] = new int[n];
}
for (i = 0; i < m; i++)
for (j = 0; j < n; j++)
std::cin >> matrix[i][j];
//-------------------------------------------------------------------------
// For local machine in Visual Studio testing
//-------------------------------------------------------------------------
/*
int i, j, k;
m = 10;
n = 8;
r = 40;
int **matrix = new int*[m];
for (int i = 0; i < m; ++i) {
matrix[i] = new int[n];
}
k = 1;
for (i = 0; i < m; i++)
for (j = 0; j < n; j++)
{
matrix[i][j] = k;
k += 1;
}
for (i = 0; i < m; i++)
for (j = 0; j < n; j++)
{
std::cout << matrix[i][j] << " ";
if (j == n - 1)
std::cout << endl;
}
std::cout << endl;
*/
//-------------------------------------------------------------------------
// Begin computations
//-------------------------------------------------------------------------
int outer_loop_rotation;
outer_loop_rotation = (n - 1) + (m - 1) + (n - 1) + (m - 1) ;
rot = r % outer_loop_rotation;
// std::cout << endl << endl << "outer loop rotation = " << outer_loop_rotation << endl << endl << "rot = " << rot << endl << endl;
for (rotations = 1; rotations <= rot; rotations++)
{
m_start = 0;
m_end = m - 1;
n_start = 0;
n_end = n - 1;
m_len = m_end - m_start;
n_len = n_end - n_start;
// Following while loop is 1 rotation for all loops
while (m_len >= 1 && n_len >= 1)
{
int loop_start = matrix[m_start][n_start];
// Following for loop is for row start
m_curr = m_start;
n_curr = n_start;
for (i = 1; i <= n_len ; i++)
{
matrix[m_curr][n_curr] = matrix[m_curr][n_curr + 1];
n_curr += 1;
}
// Following for loop is for col end
m_curr = m_start;
n_curr = n_end;
for (i = 1; i <= m_len ; i++)
{
matrix[m_curr][n_curr] = matrix[m_curr + 1][n_curr];
m_curr += 1;
}
// Following for loop is for row end
m_curr = m_end;
n_curr = n_end;
for (i = 1; i <= n_len ; i++)
{
matrix[m_curr][n_curr] = matrix[m_curr][n_curr - 1];
n_curr -= 1;
}
// Following for loop is for col start
m_curr = m_end;
n_curr = n_start;
for (i = 1; i <= m_len ; i++)
{
if (i < m_len )
{
matrix[m_curr][n_curr] = matrix[m_curr - 1][n_curr];
m_curr -= 1;
}
else
{
matrix[m_curr][n_curr] = loop_start;
}
}
m_start += 1;
m_end -= 1;
n_start += 1;
n_end -= 1;
m_len = m_end - m_start;
n_len = n_end - n_start;
} // End while loop
} // End for loop
// End computations, now output to command line
for (i = 0; i < m; i++)
for (j = 0; j < n; j++)
{
std::cout << matrix[i][j] << " ";
if (j == n - 1)
std::cout << endl;
}
return 0;
}