Write a function to find the longest common prefix string amongst an array of strings.
题目:在一个字符串数组中,求最长的初始串。
思路:先比较前两个,得到最长初始子串,之后拿这个子串去和第三个相比较,以此类推;
public String longestCommonPrefix(String[] s) {
if(s.length == 0){
return "";
}
String max = s[0];
for(int i = 0 ;i < s.length;i++) {
max = longest(max , s[i]);
}
return max;
}
public String longest(String s1, String s2){
String min = null;
String max = null;
if(s1.length() > s2.length()) {
min = s2;
max = s1;
} else {
min = s1;
max = s2;
}
for(int i = 0;i < min.length();i++) {
if(min.charAt(i) != max.charAt(i)){
return min.substring(0, i);
}
}
return min;
}