How the program is executed when there are functions?

#include <stdio.h>

int sum(int i, int j);

main()

{

int a, b, res;

a = 1;

b = 2;

res = sum(a, b);

printf("%d + %d = %d\n", a, b, res);

}

int sum(int i, int j)

{

int k;

k = i + j;

return k;

}

a b res

a, b, res have no defined values just after declaration.

a b res

1

2

a b res i j

1

2

1

2

res

3

res is set to 3 after the function call returns.

Copies are made to new memory locations for the parameter i and j in sum() function.

k i j

3

1

2

Value 3 is sent back as the value of the expression sum(a,b) in calling function.

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