Programming: A lookup table example in C

Sometimes it is better to replace a code snippet performing calculations by a lookup table. The use cases are:
1. When the result of calculation is always a member of predefined set of numbers
2. When input is a set of predefined integers

For such cases it is easy and convenient to define an array and use it. one such example is (the code can be found here):

#include <stdio.h>
	int main(void) {
	int lookupTable[4][5] = {
	{ -1, 9, 4, -1, 0 },
	{-1, -1, 9, -1, 4},
	{-1, -1, -1, -1, 5},
	{-1, -1, -1, -1, 9}
	};
	int row, columns;
	for(row=0; row < 4; row++) {
	for(columns = 0; columns < 5; columns++){
	printf("Row %d Columns %d Value %d\n", row, columns, lookupTable[row][columns]);
	}
	}
	return 0;
	}