c++ - Why wouldn't this program change anything, but the one below it does? -


i'm studying pointers in c++ upcoming exam , don't know why first code here doesn't swap values second 1 does. if explain me why great.

why wouldn't program swap values of b[0] , b[1]:

#include <iostream> using namespace std;  void func1 (int* x, int *y) {     int* temp = x;     x = y;     y = temp; }  int main() {     int b[6] = { 1, 2, 3, 4, 5, 6};     func1(&b[0], &b[1]);     cout << b[0] << b[1]; }

but 1 does:

#include <iostream> using namespace std;  void func2(int* x, int *y) {     int temp = *x;     *x = *b;     *y = temp; }  int main() {     int b[6] = { 1, 2, 3, 4, 5, 6};     func2(&b[0], &b[1]);     cout << b[0] << b[1]; }

thank :d

the explanation in first case exchanging pointers values, not pointed values themselves. you're manipulating addresses in first case, while in second case, manipulate values.


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