383.判断一个字符串是否能够包含另外一个字符串 Ransom Note

Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function that will return true if the ransom note can be constructed from the magazines ; otherwise, it will return false.

Each letter in the magazine string can only be used once in your ransom note.

Note:
You may assume that both strings contain only lowercase letters.

canConstruct("a", "b") -> false
canConstruct("aa", "ab") -> false
canConstruct("aa", "aab") -> true

1. static public bool CanConstruct(string ransomNote, string magazine) {
2. Dictionary<char, int> d = new Dictionary<char, int>();
3. char[] mArr = magazine.ToCharArray();
4. int mArrLength = mArr.Length;
5. for (int i = 0; i < mArrLength; i++) {
6. char c = mArr[i];
7. int v = 0;
8. if (d.TryGetValue(c, out v)) {
9. d[c] = v + 1;
10. } else {
11. d.Add(c, 1);
12. }
13. }
14. char[] rArr = ransomNote.ToCharArray();
15. int rArrLength = rArr.Length;
16. for (int i = 0; i < rArrLength; i++) {
17. char c = rArr[i];
18. int v = 0;
19. if (!d.TryGetValue(c, out v) || v == 0) {
20. return false;
21. } else {
22. d[c] -= 1;
23. }
24. }
25. return true;
26. }

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转载于:https://www.cnblogs.com/xiejunzhao/p/5fc18f4138f6764e1778a7fcd6245109.html