01两数之和

var twoSum = function (nums, target) {
    for (let i = 0; i < nums.length; i++) {
        let test = nums.indexOf(target - nums[i]);
        if (test != -1 && test != i) {
            return [i, test];
        }
    }
}
console.log(twoSum([2, 7, 11, 15], 9)); //[0,1]

var twoSum = (nums, target) => {
    let map = new Map();
    for (let i = 0; i < nums.length; i++) {
        if (map.has(target - nums[i])) {
            return [map.get(target - nums[i]), i]
        } else {
            map.set(nums[i], i)
        }
    }
}