Problem Statement
A pointer in C is a way to share a memory address among different contexts (primarily functions). They are primarily used whenever a function needs to modify the content of a variable, of which it doesn't have ownership.
In order to access the memory address of a variable, val, we need to prepend it with & sign. E.g., ‘‘&val" returns the memory address of val.
This memory address is assigned to a pointer and can be shared among various functions. E.g. int∗p=&val will assign the memory address of val to pointer p. To access the content of the memory to which the pointer points, prepend it with a ‘‘∗". For example, ∗p will return the value reflected by val and any modification to it will be reflected at the source (val).
You have to complete the function void update(int *a,int *b), which reads two integers as argument, and sets a with the sum of them, and b with the absolute difference of them.
In order to access the memory address of a variable, val, we need to prepend it with & sign. E.g., ‘‘&val" returns the memory address of val.
This memory address is assigned to a pointer and can be shared among various functions. E.g. int∗p=&val will assign the memory address of val to pointer p. To access the content of the memory to which the pointer points, prepend it with a ‘‘∗". For example, ∗p will return the value reflected by val and any modification to it will be reflected at the source (val).
void increment(int *v) {
(*v)++;
}
int main() {
int a;
scanf("%d", &a);
increment(&a);
printf("%d", a);
return 0;
}
You have to complete the function void update(int *a,int *b), which reads two integers as argument, and sets a with the sum of them, and b with the absolute difference of them.
- a′=a+b
- b′=|a−b|
Input Format
Input will contain two integers, a and b, separated by a newline.
Output Format
You have to print the updated value of a and b, on two different lines.
P.S.: Input/ouput will be automatically handled. You only have to complete the void update(int *a,int *b) function.
P.S.: Input/ouput will be automatically handled. You only have to complete the void update(int *a,int *b) function.
Sample Input
4
5
Sample Output
9
1
Explanation
- a′=4+5=9
- b′=|4−5|=1HERE BELOW THE SOLUTION
- TWO POINTERS CAN NEVER BE ADDED BUT CAN BE SUBTRACTED
void update(int *a,int *b) { // Complete this function
int r1=*a+*b; int r2; if(*a<*b){ r2=*b-*a; } else r2=*a-*b; *a=r1; *b=r2; }
int r1=*a+*b; int r2; if(*a<*b){ r2=*b-*a; } else r2=*a-*b; *a=r1; *b=r2; }
int main() {
int a, b;
int *pa = &a, *pb = &b;
scanf("%d %d", &a, &b);
update(pa, pb);
printf("%d\n%d", a, b);
return 0;
}
int a, b;
int *pa = &a, *pb = &b;
scanf("%d %d", &a, &b);
update(pa, pb);
printf("%d\n%d", a, b);
return 0;
}
THIS IS A QUESTION FROM A WEBSITE .
I M ONLY USE THIS AS FOR EDUCATIONAL PURPOSE ONLY',SO THAT READERS OF MY BLOG ALSO LEARN ABOUT THE SAME CONCEPT.
SREADING KNOWLEDGE
I LIKE THIS QUESTION VERY MUCH .
