Unable to access values while passing 2-D pointer

Question

I have the following code :

int allocationMatrix[2+ 1][1+ 1];
    allocationMatrix[0][0] = 2;
    allocationMatrix[0][1] = 1;
    buildAllocationMatrix(flowNProcess, allocationMatrix); 

The buildAllocationMatrix function is declared like:

void buildAllocationMatrix(FlowNProcess *flowNProcess, int *allocationMatrix)  

inside it, if I check the value of *(allocationMatrix+1), it gives 0 but the assignment
before calling the function is allocationMatrix[0][1] = 1; Not sure why its giving 0
It should return 1. What could be the reason for this?

Answer 1

• Pass int **allocationMatrixinside function since it is 2D array.

(becauseint *allocationMatrix is interpreted as passing address of 1D array) .

• And access it by *(*(allocationMatrix+0)+1).

(Reason: by using*(allocationMatrix+0) you will get address of 0th row and in order to get address of 0th row 1st column we can use (*(allocationMatrix+0)+1) thus to get element of that position dereference it as *(*(allocationMatrix+0)+1) ).

While accessing you can skip zero.