What is the output of the program? #include<stdio.h> int main() { union a { int i; char ch[2]; }; union a u; u.ch[0] = 3; u.ch[1] = 2; printf("%d, %d, %d\n", u.ch[0], u.ch[1], u.i); return 0; }

Your defined union have two members…

1) int =====================> size =4 B

2) character array of length 2 ===> size =2 B

Therefore size of Union is 4B

You updated the Char member of Union at last ===> Character array is having the original value.

what about ” int ” ? (assume your system is following little endian)

it access the total 4B ===> ch[1] ch[0] ====> 00000010 00000011 ===> 512+3 = 515

if you have the doubt that why not accessing in the form of ch[0] ch[1] ====> 00000011 00000010 ===> 512+256+2 = 770