distinct.js

function distinct(arr, t) {
  let count = 0;
  let n = arr.length;
  if(arr[n-1]<arr[n-2]){
    let s = arr[n-1];
    arr[n-1] = arr[n-2];
    arr[n-2] = s;
  }
  for(var i=0;i<n-1;i++){
    for(var j=i+1;j<=n;j++){
      if(arr[i]<arr[j] && arr[i]+arr[j]===t){
        count++
      }
    }
  }
  return count++;
}
console.log(distinct([5,3,47,3,2,9],47))