Frequency of a substring in a string | Simple python program to count occurrences of pat in txt . ; A loop to slide pat [ ] one by one ; For current index i , check for pattern match ; if pat [ 0. . . M - 1 ] = txt [ i , i + 1 , ... i + M - 1 ] ; Driver Code
def countFreq ( pat , txt ) : NEW_LINE INDENT M = len ( pat ) NEW_LINE N = len ( txt ) NEW_LINE res = 0 NEW_LINE for i in range ( N - M + 1 ) : NEW_LINE INDENT j = 0 NEW_LINE while j < M : NEW_LINE INDENT if ( txt [ i + j ] != pat [ j ] ) : NEW_LINE INDENT break NEW_LINE DEDENT j += 1 NEW_LINE DEDENT if ( j == M ) : NEW_LINE INDENT res += 1 NEW_LINE j = 0 NEW_LINE DEDENT DEDENT return res NEW_LINE DEDENT if __name__ == ' _ _ main _ _ ' : NEW_LINE INDENT txt = " dhimanman " NEW_LINE pat = " man " NEW_LINE print ( countFreq ( pat , txt ) ) NEW_LINE DEDENT