Question

i declare a dynamic array int *idArray; and i want to copy the value to a tempArray, then i will change the order of tempArray, but i don’t want to change the order idArray, how can i write it? I have tried to implement it, but when the order of tempArray be changed, the order of idArray also change.

int *idArray = new int[size]; 
int *tempArray = idArray;
int m, n;
for(int k = 0; k < size; k++) {
    m = rand() % size;
    n = tempArray[m];
    tempArray[m] = tempArray[k];
    tempArray[k] = n; 
}

Answer 1

std::vector<int> idArray(size); 
std::vector<int> tempArray = idArray;

Problemo solvo.

Also, you can use std::random_shuffle– you don’t have to shuffle the vector yourself.