一、题目：
n MATLAB, there
is a very useful function called 'reshape', which can reshape a matrix
into a new one
with different size
but keep
its original data.
You're
given a matrix represented
by a two-dimensional array,
and two positive integers r
and c representing
the row
number and column
number of the wanted reshaped matrix, respectively.
The reshaped matrix need
to be filled
with all
the elements
of the original matrix
in the same row-traversing order
as they were.
If
the 'reshape' operation
with given parameters
is possible
and legal, output
the new reshaped matrix; Otherwise, output
the original matrix.
Example
1:
Input:
nums =
[[
1,
2],
[
3,
4]]
r =
1, c =
4
Output:
[[
1,
2,
3,
4]]
Explanation:
The row-traversing
of nums
is [
1,
2,
3,
4]. The new reshaped matrix
is a
1 *
4 matrix, fill
it row
by row
by using
the previous
list.
Example
2:
Input:
nums =
[[
1,
2],
[
3,
4]]
r =
2, c =
4
Output:
[[
1,
2],
[
3,
4]]
Explanation:
There
is no way
to reshape a
2 *
2 matrix
to a
2 *
4 matrix. So output
the original matrix.
Note:
The height
and width
of the given matrix
is in range [
1,
100].
The
given r
and c are all positive.
二、解法：
class Solution {
public:
vector<vector<int>> matrixReshape(
vector<vector<int>>& nums,
int r,
int c)
{
int m = nums.size(), n = nums[
0].size(), o = m * n;
if (r * c != o)
return nums;
vector<vector<int>> res(r,
vector<int>(c,
0));
for (
int i =
0; i < o; i++) res[i / c][i % c] = nums[i / n][i % n];
return res;
}
};
