Set Matrix Zeroes

Did you use extra space?
A straight forward solution using O (mn) space is probably a bad idea.
A Simple Improvement uses O (m + n) space, but still is not the best solution.
Could you devise a constant space solution?

1,o (mn), which uses a matrix of the same size to record 0 of that position.

2,o (m + n) is a row of columns to mark which row has 0.

3, constant space, that is, consider not using extra space, you can use the first row and the first column as the marker row and the tag column, but first determine whether the first row and the first column itself should be set to 0.

classSolution { Public:    voidSetzeroes (vector<vector<int>>&matrix) {       if(Matrix.size () <1)return; introw = Matrix.size (), col = matrix[0].size (); BOOLR0 =false, C0 =false;  for(inti =0; i < row; ++i) {if(matrix[i][0] ==0) {C0=true; Break; }         }          for(intj =0; J < Col; ++j) {if(matrix[0][J] = =0) {R0=true; Break; }         }          for(inti =1; i < row; ++i) { for(intj =1; J < Col; ++j) {matrix[i][0] = (Matrix[i][j] = =0) ?0: matrix[i][0]; matrix[0][J] = (matrix[i][j] = =0) ?0: matrix[0][j]; }            }          for(inti =1; i < row; ++i) { for(intj =1; J < Col; ++j) {Matrix[i][j]= (matrix[i][0] ==0) ?0: Matrix[i][j]; MATRIX[I][J]= (matrix[0][J] = =0) ?0: Matrix[i][j]; }            }          for(inti =0; I < row && C0; ++i) matrix[i][0] =0;  for(intj =0; J < Col && R0; ++J) matrix[0][J] =0; }};

Set Matrix Zeroes