public int findPeakElement(int[] nums) {

if (nums == null || nums.length == 0) return -1;

if (nums.length == 1) return 0;

if (nums[0] > nums[1]) {

return 0;

} else if (nums[nums.length-1] > nums[nums.length-2]) {

return nums.length-1;

} else {

for (int i=1; i<nums.length-1; i++) {

if (nums[i] > nums[i-1] && nums[i] > nums[i+1]) return i;

}

}

return -1;

}

/**

public int findPeakElement2(int[] nums) {

for (int i = 0; i < nums.length - 1; i++) {

if (nums[i] > nums[i + 1])

return i;

}

return nums.length - 1;

}

public int findPeakElement3(int[] nums) {

return search(nums, 0, nums.length - 1);

}

public int search(int[] nums, int l, int r) {

if (l == r)

return l;

int mid = (l + r) / 2;

if (nums[mid] > nums[mid + 1])

return search(nums, l, mid);

return search(nums, mid + 1, r);

}

public int findPeakElement4(int[] nums) {

int l = 0, r = nums.length - 1;

while (l < r) {

int mid = (l + r) / 2;

if (nums[mid] > nums[mid + 1])

r = mid;

else

l = mid + 1;

}

return l;

}