Programming

Question

main() {
char s[]={'a','b','c','\n','c','\0'};
char *p,*str,*str1;
p=&s[3];
str=p;
str1=s;
printf("%d",++*p+++*str1-32);
}

output is 76 pls explain.

Comments

answer should be 77

Answer 1

1) char s[]={'a','b','c','\n','c','\0'}; 

by this line s is array of characters created at location 100 ( assume)

'a'	'b'	'c'	'\n'	'c'	'\n'
100	101	102	103	104	105

 

2) char *p,*str,*str1; 

 by this line you are declaring p is pointer to character, str is pointer to character, str1 is pointer to character

 

3) p=&s[3]; 

by this line p is get value as memory address of 3rd index of s ===> p = 103

4)str=p; 
by this line str also get value as memory address of 3rd index of s ===> str = 103

 

5) str1=s; 

by this line str1 get value as memory address of 0th index of s ===> str1 = 100

6) ++*p+++*str1-32  =====>  (++*p+++*str1) - ( 32 )   =====>  (  (++ ( * (p ++) ) )  + ( * str1) ) - ( 32 ) 

p is post increment ===> no change in that statement ===> p=103 ===> *p = value at 103 ==> '\n'

(++ ( * (p ++) )  ===> increment the value = '\n' + 1 ===> ascii value of '\n' +1 = 10+1 =11 

 

(++*p+++*str1) - ( 32 )  = 11 + 'a' - 32 ===> 11+97-32 = 108 - 32 = 76

Comments

thanks