Pointer C++
Problem Statement :
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 val in 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 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
Solution :
Solution in C :
#include <stdio.h>
#include <iostream>
#include <cmath>
using namespace std;
void update(int *a,int *b) {
int c = *a;
*a = *a + *b;
*b = fabs(c-*b);
}
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;
}
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