function twoSum(nums,target){
const map=new Map()
for(let i=0;i<nums.length;i++){
const complete=target-nums[i]
if(map.has(complete)){
return [map.get(complete),i]
}else{
map.set(nums[i],i)
}
}
}
console.log(twoSum([3,1,4,6],9))