DSA/0023searching.cpp at main · Ashish-Waykar/DSA · GitHub

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//jump search
#include<iostream>
#include<math.h>
using namespace std;
int jumpSearch(int arr[], int x, int n)
{
    // Finding block size to be jumped
    int step = sqrt(n);

    // Finding the block where element is
    // present (if it is present)
    int prev = 0;
    while (arr[min(step, n)-1] < x)
    {
        prev = step;
        step += sqrt(n);
        if (prev >= n)
            return -1;
    }

    // Doing a linear search for x in block
    // beginning with prev.
    while (arr[prev] < x)
    {
        prev++;

        // If we reached next block or end of
        // array, element is not present.
        if (prev == min(step, n))
            return -1;
    }
    // If element is found
    if (arr[prev] == x)
        return prev;

    return -1;
}
// int jumpSearch(int arr[],int x,int n){
//     int step = sqrt(n);
//     int prev =0;
//     while (arr[min(step,n)-1]<x)
//     {
//         prev = step;
//         step+=sqrt(n);
//         if(prev>=n){return -1;}
//     }
//     while(arr[prev] < x){
//         prev++;
//         if(prev == min(step,n));
//         return -1;
//     }
//     if (arr[prev] == x){
//         return prev;
//     }
//     return -1;
// }

int main(){
    int arr[]= {0,1,1,2,3,5,8,13,21,34,55,89,144,233,377,610};
    int x = 55;
    int n = sizeof(arr)/sizeof(arr[0]);
    int index = jumpSearch(arr,x,n);
    cout << " Number "<<x<<" is At index "<<index ;
    return 0;
}