Matrix Arithmetic using Vectors in C++ causing segmentation faults

Question

I\'m having some issues passing vectors to functions. My concern is not with my logic itself, as if I need to adjust later I will. My program requirements state that I must

Answer 1

int row=0, col=0;
vector > matrix(row, vector (col) );
vector > matrix2(row, vector (col) );
vector > matrix3(row, vector (col) );

This creates the vectors while row and col are still zero, long before you read in the values.