code-2pointer.cpp

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 *
 * Code for the book "DAILY 43: Algorithmic Problems for Coding Interviews: Easy level, C++ edition"
 *
 * Licensed under the GNU General Public License, Version 3.0 (the "License");
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#include <iostream>
#include <vector>
#include <algorithm> // For std::swap

void moveZeroesToEnd(std::vector<int>& nums) {
    // i moves through all elements
    // j moves over non-zero elements only
    int i = 0, j = 0;
    while (i < nums.size() && j < nums.size()) {
        if (nums[i] != 0) {
            std::swap(nums[j++], nums[i++]);
        } else {
            ++i;
        }
    }
}

int main() {
    std::vector<int> nums = {0, 1, 0, 3, 12}; // Example input
    moveZeroesToEnd(nums);
    std::cout << "Array after moving zeroes to the end: ";
    for (int num : nums) {
        std::cout << num << " ";
    }
    std::cout << std::endl;
    return 0;
}