704. 二分查找（算法200题-22）

/**
 * @param {number[]} nums
 * @param {number} target
 * @return {number}
 */
var search = function(nums, target) {
    const length = nums.length
    let center = 0,
        left = 0,
        right = length -1
    while(left <= right) { 
        center = Math.floor((right - left) / 2) + left
        if(nums[center] === target) return center
        if(nums[center] > target) {
            right = center - 1
        } else {
            left = center + 1
        }
    }
    return -1
};