1p1 (int b, int *p, int a) 2{ 3 p[0] = p[1]; 4 return p[0]; 5} 6p2 (int b, int *p, int a) 7{ 8 p[0] = p[1]; 9 return p[0] == 0; 10} 11p3 (int b, int *p, int a) 12{ 13 p[0] = p[1]; 14 a = p[0]; 15 if (a) 16 return 0; 17 return a; 18} 19p4 (int b, int *p, int a) 20{ 21 a = p[1]; 22 p[0] = p[1]; 23 if (a) 24 return 0; 25 return a; 26} 27