in the brute force pattern matching algorithm when all the characters in the pattern are unique then brute force can be implemented in Big-oh(n) complexity where n is the length of the string( reference :introduction to algorithms).

can anyone help me with the algorithm? thanks in advance

# brute force pattern matching algorithm

**saimadan**#1

**infinitum**#2

Yes we can do pattern Matching in O(n) Complexity given that all the characters in the pattern are unique.

**Algorithm** (self explanatory *python Code*):

Let the pattern be P of Length PL and Source String be S of Length SL

```
S = raw_input()
P = raw_input()
SL = len(S)
PL = len(P)
if PL > SL:
print("No Match Found")
else:
Found = False
for i in range(0,SL):
j = 0
while j < PL and S* == P[j] :
i=i+1
j=j+1
if j == PL:
Found = True
print("Matching Found At " + str(i-PL+1))
if not Found:
print("No Matching Found")
```

Code prints all the positions where the pattern starts