Calculating execution time of different sorting algorithms using clock()

sorting_time.cpp

#include<iostream>
#include<ctime>
using namespace std;

void bubbleSort1(int*,int);
void bubbleSort2(int*,int);
void bubbleSort3(int*,int);
void insertionSort(int*,int);
void selectionSort(int*,int);
void doSwap(int*,int*);
void printArray(int*,int);


int main(){
    int arr1[10] = {10,9,8,6,4,3,1,2,5,7};
    int arr2[10] = {10,9,8,6,4,3,1,2,5,7};
    int arr3[10] = {10,9,8,6,4,3,1,2,5,7};
    int arr4[10] = {10,9,8,6,4,3,1,2,5,7};
    int arr5[10] = {10,9,8,6,4,3,1,2,5,7};
    int N = 10;
    int start_time,stop_time;

    start_time = clock();
    insertionSort(arr1,N);
    stop_time = clock();
    cout<<"Insertion sort time: "<<(stop_time-start_time)/double(CLOCKS_PER_SEC)*1000<<endl;

    start_time = clock();
    selectionSort(arr2,N);
    stop_time = clock();
    cout<<"Selection sort time: "<<(stop_time-start_time)/double(CLOCKS_PER_SEC)*1000<<endl;

    start_time = clock();
    bubbleSort1(arr3,N);
    stop_time = clock();
    cout<<"BubbleSort 1 time: "<<(stop_time-start_time)/double(CLOCKS_PER_SEC)*1000<<endl;

    start_time = clock();
    bubbleSort2(arr4,N);
    stop_time = clock();
    cout<<"BubbleSort 2 time: "<<(stop_time-start_time)/double(CLOCKS_PER_SEC)*1000<<endl;


    start_time = clock();
    bubbleSort2(arr5,N);
    stop_time = clock();
    cout<<"BubbleSort 3 time: "<<(stop_time-start_time)/double(CLOCKS_PER_SEC)*1000<<endl;


    //printArray(arr3,N)
    //printArray(arr2,N);
    //printArray(arr3,N);
}

//selection sort
void selectionSort(int* arr,int N){

    for(int i=0;i<N;i++){
        int minNum = arr[i];
        int minKey = i;
        for(int j=i+1;j<N;j++){
            if(arr[j] < minNum){
               minNum = arr[j];
               minKey = j;
            }
        }
        int temp = arr[i];
        arr[i] = minNum;
        arr[minKey] = temp;
    }
}
//insertion sort
void insertionSort(int* arr,int N){
    for(int i=1;i<N;i++){
        int key = arr[i];
        int j = i-1;
        while(j>=0 && key<arr[j]){
            arr[j+1] = arr[j];
            j--;
        }
        arr[j+1] = key;
    }
}

//bubble sort 1
void bubbleSort1(int* arr,int N){
    for(int i=1;i<N;i++){
        for(int j=0;j<N-1;j++){
            if(arr[j+1] < arr[j]){
                doSwap(&arr[j+1],&arr[j]);
            }
        }
    }
}
//bubble sort 2
void bubbleSort2(int* arr,int N){
    for(int i=1;i<N;i++){
        int swaps = 0;
        for(int j=0;j<N-1;j++){
            if(arr[j+1] < arr[j]){
                doSwap(&arr[j+1],&arr[j]);
                swaps++;
            }
        }
        if(swaps == 0){
            break;
        }
    }
}

//bubble sort 3
void bubbleSort3(int* arr,int N){
    for(int i=1;i<N;i++){
        int swaps = 0;
        for(int j=0;j<N-i;j++){
            if(arr[j+1] < arr[j]){
                doSwap(&arr[j+1],&arr[j]);
                swaps++;
            }
        }
        if(swaps == 0){
            break;
        }
    }
}

//swap fuction
void doSwap(int* x,int* y){
    int temp = *x;
    *x = *y;
    *y = temp;
}

//print function
void printArray(int* arr,int N){
    for(int i=0;i<N;i++){
        cout<<arr[i]<<" ";
    }
}