leetcode-14. Longest Common Prefix
Write a function to find the longest common prefix string amongst an array of strings.
最长的子序列一定是一个序列的子集,不可能比这个array中任何一个string要长
class Solution {
public:
string longestCommonPrefix(vector<string>& strs) {
if(strs.empty()) return ""; //IMPORTANT!!!
string res = "";
for(int i = 0; i < strs[0].size(); ++i){
char c = strs[0][i];
for(int j = 1; j < strs.size(); ++j){
if(i > strs[j].size() || strs[j][i] != c){
return res;
}
}
res.push_back(c);
}
return res;
}
};