4 examples of 'find letters in string python' in Python

1
def count_letters(string):
2
    freq, limit, i = {}, len(string), 0
3
    while i < limit:
4
        if string[i] in freq:
5
            freq[string[i]] += 1
6
        else:
7
            freq[string[i]] = 1
8
        i += 1
9
    return freq

5
def reverseOnlyLetters(self, S):
6
    """
7
    :type S: str
8
    :rtype: str
9
    """
10
    def getNext(S):
11
        for i in reversed(xrange(len(S))):
12
            if S[i].isalpha():
13
                yield S[i]
14
15
    result = []
16
    letter = getNext(S)
17
    for i in xrange(len(S)):
18
        if S[i].isalpha():
19
            result.append(letter.next())
20
        else:
21
            result.append(S[i])
22
    return "".join(result)

2
def firstUniqChar(self, s):
3
    """
4
    :type s: str
5
    :rtype: int
6
    """
7
    counts = [0] * 26
8
    for item in s:
9
        counts[ord(item) - ord('a')] += 1
10
    for (index, item) in enumerate(s):
11
        if counts[ord(item) - ord('a')] == 1:
12
            return index
13
    return -1

42
def firstUniqChar(self, s):
43
	"""
44
	:type s: str
45
	:rtype: int
46
	"""
47
	alphabet = 'abcdefghijklmnopqrstyvwxyz'
48
	index = len(s)
49
	for c in alphabet:
50
		if c in s:
51
			l = s.find(c)
52
			r = s.rfind(c)
53
		else:
54
			continue
55
		if l == r and l < index:
56
			index = l
57
	if index == len(s):
58
		return -1
59
	return index