LeetCode Minimum Window Substring
2017-01-13 15:26
267 查看
Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).
For example,
S =
T =
Minimum window is
Note:
If there is no such window in S that covers all characters in T, return the empty string
If there are multiple such windows, you are guaranteed that there will always be only one unique minimum window in S.
思路一:最小滑动窗口方法,与substring with concatenation of all words的方法类似.
class Solution {
public:
string minWindow(string s, string t) {
string result="";
if(s.empty() || t.empty())
return result;
unordered_map<char,int> map,newMap;
for(int i=0;i<t.length();i++)
map[t[i]]++;
int min=0x7fffffff;
int start=0,end,count=0;
int sLen = s.length(),tLen = t.length();
for(end=0;end<sLen;end++)
{
if(map.find(s[end]) != map.end())
{
if(newMap[s[end]] < map[s[end]])
{
count++;
}
newMap[s[end]]++;
if(count == tLen)
{
while(map.find(s[start]) == map.end() || newMap[s[start]] > map[s[start]])
{
newMap[s[start]]--;
start++;
}
if(end-start+1 < min)
{
min = end-start+1;
result =s.substr(start,min);
}
}
}
}
return result;
}
};
For example,
S =
"ADOBECODEBANC"
T =
"ABC"
Minimum window is
"BANC".
Note:
If there is no such window in S that covers all characters in T, return the empty string
"".
If there are multiple such windows, you are guaranteed that there will always be only one unique minimum window in S.
思路一:最小滑动窗口方法,与substring with concatenation of all words的方法类似.
class Solution {
public:
string minWindow(string s, string t) {
string result="";
if(s.empty() || t.empty())
return result;
unordered_map<char,int> map,newMap;
for(int i=0;i<t.length();i++)
map[t[i]]++;
int min=0x7fffffff;
int start=0,end,count=0;
int sLen = s.length(),tLen = t.length();
for(end=0;end<sLen;end++)
{
if(map.find(s[end]) != map.end())
{
if(newMap[s[end]] < map[s[end]])
{
count++;
}
newMap[s[end]]++;
if(count == tLen)
{
while(map.find(s[start]) == map.end() || newMap[s[start]] > map[s[start]])
{
newMap[s[start]]--;
start++;
}
if(end-start+1 < min)
{
min = end-start+1;
result =s.substr(start,min);
}
}
}
}
return result;
}
};
相关文章推荐
- leetcode 76 Minimum Window Substring
- LeetCode Minimum Window Substring
- leetcode - Minimum Window Substring
- Leetcode Minimum Window Substring
- LeetCode Minimum Window Substring
- [LeetCode] Minimum Window Substring
- [leetcode]Minimum Window Substring
- LeetCode()Minimum Window Substring 超时,但觉得很清晰。
- Leetcode:Minimum Window Substring
- LeetCode76 Minimum Window Substring(两种解法)
- Minimum Window Substring @LeetCode
- Minimum Window Substring(leetcode)
- LeetCode:Minimum Window Substring
- LeetCode刷题笔记(贪心):minimum-window-substring
- leetcode:Minimum Window Substring 细致分析
- [LeetCode] Minimum Window Substring
- [LeetCode] Minimum Window Substring
- LeetCode(76) Minimum Window Substring
- minimum_window_substring ——leetcode
- LeetCode: Minimum Window Substring