2022.05.29(LC_6078_重排字符形成目标字符串)

方法：计数

class Solution {
    public int rearrangeCharacters(String s, String target) {
        Map<Character, Integer> tMap = new HashMap<>();
        for (char ch : target.toCharArray()) {
            tMap.put(ch, tMap.getOrDefault(ch, 0) + 1);
        }
        Map<Character, Integer> sMap = new HashMap<>();
        for (char ch : s.toCharArray()) {
            sMap.put(ch, sMap.getOrDefault(ch, 0) + 1);
        }
        int ans = 0;
        boolean flag = true;
        while (flag) {
            for (char ch : tMap.keySet()) {
                if (sMap.get(ch) != null && sMap.get(ch) >= tMap.get(ch)) {
                    sMap.put(ch, sMap.get(ch) - tMap.get(ch));
                } else {
                    flag = false;
                    break;
                }
            }
            if (flag) ans++;
        }
        return ans;
    }
}

 

class Solution {
    public int rearrangeCharacters(String s, String target) {
        int[] count1 = new int[26];
        int[] count2 = new int[26];
        int ans = Integer.MAX_VALUE;
		for (char ch : s.toCharArray()) {
			count1[ch - 'a']++;
		}
		for (char ch : target.toCharArray()) {
			count2[ch - 'a']++;
		}
		for (char ch : target.toCharArray()) {
			ans = Math.min(ans, count1[ch - 'a'] / count2[ch - 'a']);
		}
		return ans;
    }
}