occurences of substring in a String python

Description

python program to get a String and Substring and count the occurrence of substring in string.
Input:
entertainment
en
Ouput:
2

Solution

s1=input("Enter a String:")
s2=input("Enter Substring:")
count=0
for i in range(0,len(s1)-len(s2)+1):
    j=0
    b=0
    if(s1[i]==s2[j]):
        k=i
        while(j<len(s2)):
            if(s1[k]!=s2[j]):
                b=1
                break
            j=j+1
            k=k+1
        if(b==0):
            count+=1
print(count)

            
            
				

Explanation

check whether first character of sub string is equal to any character in string. If it is equal, then check remaining characters are equal to the characters in substring.  else move to next character.