1189. Maximum Number of Balloons

Problem Statement

Easy

Given a string text, you want to use the characters of text to form as many instances of the word "balloon" as possible.

You can use each character in text at most once. Return the maximum number of instances that can be formed.

Example 1:

Input: text = "nlaebolko"
Output: 1

Example 2:

Input: text = "loonbalxballpoon"
Output: 2

Example 3:

Input: text = "leetcode"
Output: 0

Constraints:

1 <= text.length <= 10⁴
text consists of lower case English letters only.

Note: This question is the same as 2287: Rearrange Characters to Make Target String.

Java

Source file

class Solution {
    public int maxNumberOfBalloons(String text) {
        int[] freq = new int[26];
        for (char c : text.toCharArray())
            freq[c - 'a']++;
        // balloon = 1b,1a,2l,2o,1n
        return Math.min(Math.min(Math.min(freq['b' - 'a'], freq['a' - 'a']),
                Math.min(freq['l' - 'a'] / 2, freq['o' - 'a'] / 2)),
                freq['n' - 'a']);
    }
}