Linear search/ Sequential search
Linear
search (also called as sequential search) is a simple search algorithm. It is
used to search a key in a list of keys. It compares each key in list starting
from the first key to the last until it finds the required key.
Example:
Index 0
1 2 3
4
20

67

11

90

19

From
the list of keys above you have to find the key 90. You are going to return whether
90 exist or not. If exists, you have to return it’s position.
Linear
search compares the key 90 with the value stored at index 0, then with the
value stored at index 1 and so on until it finds the entry that is matching
with the key or to the end of the list.
If
the key is found, it returns ‘FOUND’ and the index at which it is found. If not,
it returns ‘NOT FOUND’.
Algorithm
Algorithm
Linear (a[], total_keys, key_to_find)
{
flag
:= 0;
for
(i =0; i <= total_keys1; i++)
if (a[i] == key_to_find)
flag := 1;
if
(flag == 1)
print ‘FOUND’;
else
print ‘NOT FOUND’;
}
Algorithm Description:
Algorithm

Description

1: Linear (a[],
total_keys, key_to_find)
2: {
3: flag := 0;
4: for (i = 0; i <=
total_keys  1; i++)
5: if (a[i]
== key_to_find)
6: flag
:= 1;
7: if (flag == 1)
8: print ‘FOUND’;
9: else
10: print ‘NOT
FOUND’;
11: }

3: Set the flag with 0
4: Scans entire array from index 0 to n1
5: Compares each array element with key
6: If found, set the flag with 1
8: After array scan, if flag is 1 return FOUND
10: Else return NOT FOUND

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Linear search algorithm in data structures
Linear search using C
Sequential search algorithm
Sequential search pseudocode
Explain linear search algorithm