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linear-search

There are two type of search :

  1. linear search
  2. binary search


 0   1   2   3   4  5   6   //index
[10][34][24][36][2][9][11]  //position
---------------->

<---------------

for --- i=0 to 4

arr[i] == key

Example 1:

    #include <iostream>
    using namespace std;
    int main() {

       int arr[5] = 10,20,30,40,50;

       int key;
       cout<<"Enter key to search: ";
       cin>>key;

       for(int i=0; i<5; i++)
       {
        if(key==arr[i])
        {
            cout<<"key found at: "<<i<<endl;
        }
       }
        return 0;
    }

Output :

Enter key to search: 30
key found at: 2

Explanation :

In a line no 5 declare array that name has arr and size of array is 5;
Enter 5 Elements in Array: using cout.
In a line no 7 declare variable that name has key and datatype is int.
print Enter key to search: using cout.
In a line no 11 for(int i=0; i<5; i++) initialize i variable check condition i<5 and increase value by one.
check if(key == arr[i]) condition key is equal to arr[i] this condition are true then flag = i and print key found at:and i variable.
check next condition if(flag == -1) then print Element Not found using cout.

Example 2:

    #include <iostream>
    using namespace std;
    int main() {

       int arr[5] = {10,20,30,40,50};

       int key;
       cout<<"Enter key to search: ";
       cin>>key;

       int flag = -1;

       for(int i=0; i<5; i++)
       {
        if(key==arr[i])
        {
            flag = i;
            cout<<"Key found at: "<<i<<endl;
            break;
        }
       }
       if(flag == -1)
       {
        cout<<"Element Not found";
       }

        return 0;
    }

Output :

Enter key to search: 80
Element Not found

Explanation :

In a line no 5 declare array that name has arr and size of array is 5;
Enter 5 Elements in Array: using cout.
In a line no 7 declare variable that name has key and datatype is int.
print Enter key to search: using cout.
In a line no 11 initialized temporary variable that name has flag store value -1 and datatype is int.
In a line no 13 for(int i=0; i<5; i++) initialize i variable check condition i<5 and increase value by one.
check if(key == arr[i]) condition key is equal to arr[i] this condition are true then flag = i and print key found at:and i variable.
check next condition if(flag == -1) then print Element Not found using cout.