In a string S
of lowercase letters, these letters form consecutive groups of the same character.
For example, a string like S = "abbxxxxzyy"
has the groups "a"
, "bb"
, "xxxx"
, "z"
and "yy"
.
Call a group large if it has 3 or more characters. We would like the starting and ending positions of every large group.
The final answer should be in lexicographic order.
Example 1:
Input: "abbxxxxzzy"
Output: [[3,6]]
Explanation: "xxxx" is the single
large group with starting 3 and ending positions 6.
Example 2:
Input: "abc" Output: [] Explanation: We have "a","b" and "c" but no large group.
Example 3:
Input: "abcdddeeeeaabbbcd" Output: [[3,5],[6,9],[12,14]]
Note: 1 <= S.length <= 1000
上周比赛出的新题,自己写了一下,一遍过(小得意嘻嘻):
class Solution {
public:
vector<vector<int>> largeGroupPositions(string S) {
vector<vector<int>> output;
// 1<=s<=1000;
int cnt=0;
int start=0;
int end_loc=0;
int temp=0;
for(auto &i:S){
vector<int> loc;
temp=start;
while(i==S[temp]){
++temp;
++cnt;
}
if(cnt>=3){
loc.push_back(start);
end_loc=start+cnt-1;
loc.push_back(end_loc);
(output).push_back(loc);
}
start+=cnt;
cnt=0;
}
return output;
}
};
排版好乱。。感觉使用了tab的原因。。。