Question

Write a function named swapFrontBack that takes as input a vector of integers. The function should swap the first element in the vector with the last element in the vector. The function should check if the vector is empty to prevent errors. Test your function with vectors of different length and with varying front and back numbers.

Answer 1

#include <iostream>

#include <vector>

using namespace std;

void swapFrontBack(vector<int>& nums) {

if(nums.size() < 2) {

return;

}

swap(nums[0], nums[nums.size()-1]);

}

void printit(vector<int>& arr) {

for(int i = 0; i < arr.size(); i++) {

cout << arr[i] << " ";

}

cout << endl;

}

int main() {

vector<int> num1;

swapFrontBack(num1);

printit(num1);

num1.push_back(1);

swapFrontBack(num1);

printit(num1);

num1.push_back(2);

swapFrontBack(num1);

printit(num1);

vector<int> num2(10, 1);

num2[9] = 2;

swapFrontBack(num2);

printit(num2);

return 0;

}

Step-by-step explanation: