跳到主要内容

两数之和

暴力枚举

var twoSum = function (nums, target) {
const n = nums.length

for (let i = 0; i < n; i++) {
for (let j = 0; j < n; j++) {
if (nums[i] + nums[j] === target && i !== j) {
return [i, j]
}
}
}
}

哈希表

var twoSum = function (nums, target) {
const map = new Map()

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