1170. Compare Strings by Frequency of the Smallest Character 

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class Solution {
    public int[] numSmallerByFrequency(String[] queries, String[] words) {
        int[] minCharFrequencies = new int[words.length];
        for (int i = 0; i < words.length; i++) {
            minCharFrequencies[i] = getMinCharFrequency(words[i]);
        }

        Arrays.sort(minCharFrequencies);

        int[] res = new int[queries.length];
        for (int i = 0; i < queries.length; i++) {
            int minCharFrequency = getMinCharFrequency(queries[i]);
            res[i] = getGreatThanCount(minCharFrequencies, minCharFrequency);
        }
        return res;
    }

    private int getGreatThanCount(int[] minCharFrequencies, int target) {
        // 寻找首个大于 target 的元素索引
        int left = 0, right = minCharFrequencies.length;
        while (left < right) { // [left, right)
            int mid = (left + right) >>> 1;
            if (minCharFrequencies[mid] < target) {
                left = mid + 1;
            } else if (minCharFrequencies[mid] > target) {
                right = mid; // 注意此处缩小了搜索范围，确保不产生死循环
            } else {
                left = mid + 1;
            }
        }

        return minCharFrequencies.length - left;
    }

    private int getMinCharFrequency(String word) {
        char minChar = word.charAt(0);
        int frequency = 0;

        for (int i = 0; i < word.length(); i++) {
            char c = word.charAt(i);
            if (c < minChar) {
                minChar = c;
                frequency = 1;
            } else if (c == minChar) {
                frequency++;
            }
        }

        return frequency;
    }
}

References

1170. Compare Strings by Frequency of the Smallest Character