function twoSum(nums, target_num) {  
  var map = [];  
  var indexnum = [];  
    
  for (var x = 0; x < nums.length; x++)  
  {  
  if (map[nums[x]] != null)  
  {  
  index = map[nums[x]];  
  indexnum[0] = index+1;  
  indexnum[1] = x+1;  
  break;  
  }  
  else  
  {  
  map[target_num - nums[x]] = x;  
  }  
  }  
  return indexnum;  
  }  
console.log(twoSum([10,20,10,40,50,60,70],50));  