编辑代码

function twoSum(arr, target) {
    const map = {};
    // [1,4,3,5,7]
    for(let i = 0; i < arr.length; i++) {
        const v = target - arr[i];
        if(map[v]) {
            return [map[v], i]
        }else {
            map[arr[i]] = i;
        }
    }
    return -1;
}

const arr = [1,4,3,5,7];
console.log(twoSum(arr, 7))