题解 | #星际穿越#

一元二次方程

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void async function () {
    // Write your code here
   let h = await readline()
  // 由题意得：   x*x + x - h < 0
   let x1,x2 ,delta;
   delta = 1+ 4 * h;
   x1 = (-1 - Math.sqrt(delta))/2
   x2 = (-1 + Math.sqrt(delta))/2
   console.log(Math.floor(x2))
}()