使用二维数组创建矩阵

I've been writing a program conducting some operations on two square matrixes. For the time being I've been thinking of a code which will read a matrix of a fixed (previously known size) and I'm writing these data into a 2-D array. However, I've got a problem, because when I'm debugging my code with addictional output messages everything seems fine, but the final output (the one in the I've been writing a program conducting some ope