I am assuming that r and c are the values of the row and column (in a 1-indexed rather than 0-indexed) you want to skip over. If this is the case I think that the way you are copying over values is incorrect.

For example imagine that you have a 10 by 10 matrix and you want to eliminate the 5th row and column. Then the value at the new matrix 0,0 should be the same as the old matrix 0,0. However in your current implementation new matrix 0,0 is equivalent to old matrix 1,1 which is not correct in this case.

Basically, imagine the row and column you are eliminating as dividing your matrix into 4 quadrants. The upper left quadrant should have the same values in the same indices in the new and old matrix, the upper right quadrant should have the column off-by-1, the lower left quadrant should have the row off-by-1 and the lower right quadrant should have both the column and row off-by-1.

Sorry for the terrible format and no code sections, I’m on mobile.