I want to know the how is output come....

Question

//am beginner in C language

#include <stdio.h>

int main() {

char s1[7]="1234" ,*p;

p=s1+2;
*p='0';
printf("%s", s1);

}

//Output : 1204
https://code.sololearn.com/cwXSkYOEOC2Y/?ref=app

Answer 1

Remember to calculate offset when assigning memory address to a pointer.

Knowing <s1> content and indices

0 1 2 3 <- index
1 2 3 4 < value

The following line ...

p = s1 + 2;

Sets pointer <p> to the address of <s1> plus 2 characters. At this point, <p> points to address of 3rd character in <s1> (index 2) which is '3'.

*p = '0';

And the line above modifies the data stored at the memory address of the 3rd character from its original value '3', to '0'.

Answer 2

If you are asking for the explanation of the output:

When you create a char pointer and assign it the memory address of s1+2, you are basically assigning the memory address of the third value in the character array which is '3'. So when you change the value with *p='0'; You are changing the value of character array from "1234" to "1204"

Answer 3

Ipang Ashish Neupane thank u so much for helping me🙏🙏