How to resize array in C++?

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You cannot resize array, you can only allocate new one (with a bigger size) and copy old array’s contents.
If you don’t want to use std::vector (for some reason) here is the code to it:

int size = 10;
int* arr = new int[size];

void resize() {
    size_t newSize = size * 2;
    int* newArr = new int[newSize];

    memcpy( newArr, arr, size * sizeof(int) );

    size = newSize;
    delete [] arr;
    arr = newArr;
}

code is from here http://www.cplusplus.com/forum/general/11111/.

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