Find Minimum in Rotated Sorted Array II 旋转数组中找最小值（有重复元素） @LeetCode

递归

public class Solution {
public int findMin(int[] num) {
return helper(num, 0, num.length-1);
}

//with duplicate
public static int helper(int[] a, int left, int right){

//one element
if(left == right){
return a[left];
}

//two elements
if(left == right-1){
return a[left]<a[right]? a[left]: a[right];
}

//the array is ordered
if(a[left] < a[right]){
return a[left];
}

int mid = (left+right)/2;

if(a[mid] > a[left]){
return helper(a, mid, right);
}else if(a[mid] < a[left]){
return helper(a, left, mid);
}else{ //when a[mid] == a[left], we have to search both side
return Math.min(helper(a, mid, right), helper(a, left, mid));
}

}
}