```
public class Solution {
public String longestCommonPrefix(String[] strs) {
int len = strs.length;
if (len == 0)
return "";
int minlen = 0x7fffffff;
for (int i = 0; i < len; ++i)
minlen = Math.min(minlen, strs[i].length());
for (int j = 0; j < minlen; ++j)
for (int i = 1; i < len; ++i)
if (strs[0].charAt(j) != strs[i].charAt(j))
return strs[0].substring(0, j);
return strs[0].substring(0, minlen);
}
}
```