Q15

Consider the following C program. # include <stdio.h> void mystery (int *ptra, int *ptrb) { int *temp; temp = ptrb; ptrb =ptra; ptra = temp; } int main () { int a = 2016, b=0, c= 4, d = 42; mystery (&a, &b); if (a < c) mystery (&c, &a); mystery (&a, &d); printf("%d\n", a); } The output of the program is _________.