for(int i = 0;i < length; i++){
count[string[i] - 'a']++;
}
I have seen many people use this code to count the number of occurrences of each letter in a string.Would like to know how this code does that.
Asked
Active
Viewed 89 times
-2
-
Possible duplicate of [Counting occurences in a vector](http://stackoverflow.com/questions/1204313/counting-occurences-in-a-vector) – LogicStuff Nov 16 '15 at 09:20
-
2Which part do you don't understand ? – Jarod42 Nov 16 '15 at 09:21
-
I don't get the -'a' part – Rahul Narayanan Nov 16 '15 at 09:24
-
You should look up the ASCII table. By `c - 'a'`, you get the distance of `char c`'s value from `'a'`, which is also an index of a letter in the alphabet. – LogicStuff Nov 16 '15 at 09:28
-
+LogicStuff Thanks,now it makes sense. – Rahul Narayanan Nov 16 '15 at 09:31
1 Answers
0
Every char is a number in C++. So count[i] stores the number of occurences of i'th letter.
Murat Akburak
- 51
- 1
- 1
- 12