Pointer

A pointer in C++ is used to share a memory address among different contexts (primarily functions). They are used whenever a function needs to modify the content of a variable, but it does not have ownership.
In order to access the memory address of a variable, val, prepend it with & sign. For example, &val returns the memory address of val.
This memory address is assigned to a pointer and can be shared among functions. For example, int*p = &val assigns the memory address of val to pointer p. To access the content of the memory pointed to, prepend the variable name with a *. For example, *p will return the value stored in val and any modification to it will be performed on val.

void increment(int *v) {
    (*v)++;
}

int main() {
    int a;
    scanf("%d", &a);
    increment(&a);
    printf("%d", a);
    return 0;
}

Function Description

Complete the update function in the editor below.

update has the following parameters:

• int *a: an integer
• int *b: an integer

Returns

• The function is declared with a void return type, so there is no value to return. Modify the values in memory so that a contains their sum and b contains their absoluted difference.
• a’ = a + b
• b’ = |a -b|

Input Format

Input will contain two integers, a and b, separated by a newline.

Sample Input

4
5

Sample Output

9
1

Explanation

• a’ = 4 + 5 = 9
• b’ = |4 – 5| = 1

Solution Implementation

#include <cstdio>
#include <cstdlib>

void update(int *a,int *b) {
    int temp1 = *a + *b;
    int temp2 = abs(*a - *b);
    *a  = temp1;
    *b = temp2;
}

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;
}