forked from lennylxx/leetcode
-
Notifications
You must be signed in to change notification settings - Fork 0
/
49.cpp
91 lines (73 loc) · 2.27 KB
/
49.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
#include <iostream>
#include <vector>
#include <string>
#include <unordered_map>
using namespace std;
class Solution {
public:
/* O(n) */
vector<vector<string>> groupAnagrams(vector<string>& strs) {
unordered_map<string, vector<string>> hash;
for (int i = 0; i < strs.size(); i++) {
string word = strs[i];
sort(word.begin(), word.end());
hash[word].push_back(strs[i]);
}
vector<vector<string>> ans(hash.size());
int k = 0;
for (auto it = hash.begin(); it != hash.end(); it++, k++) {
ans[k].swap(it->second);
sort(ans[k].begin(), ans[k].end());
}
return ans;
}
/* very slow, will exceed time limit, O(n*n) */
vector<vector<string>> groupAnagrams0(vector<string>& strs) {
vector<vector<string>> ans;
vector<string> temp;
vector<bool> flag(strs.size(), false);
for (int i = 0; i < strs.size(); i++) {
if (flag[i]) continue;
flag[i] = true;
int hash[26] = {0};
string word = strs[i];
for (int k = 0; k < word.length(); k++) {
hash[word[k] - 'a'] += 1;
}
temp.push_back(word);
for (int j = i + 1; j < strs.size(); j++) {
if (flag[j]) continue;
int hasht[26] = {0};
string t = strs[j];
for (int k = 0; k < t.length(); k++) {
hasht[t[k] - 'a'] += 1;
}
/* compare hash table */
int c = 25;
while (c >= 0 && hash[c] == hasht[c]) {
c--;
}
if (c == -1) {
flag[j] = true;
temp.push_back(t);
}
}
sort(temp.begin(), temp.end());
ans.push_back(temp);
temp.clear();
}
return ans;
}
};
int main() {
vector<string> strs = {"eat", "tea", "tan", "ate", "nat", "bat"};
Solution s;
auto ans = s.groupAnagrams(strs);
for (int i = 0; i < ans.size(); i++) {
for (int j = 0; j < ans[i].size(); j++) {
cout << ans[i][j] << " ";
}
cout << endl;
}
return 0;
}