const langToConfig = {
    'javascript': {
        image: '',
        cmd: ['']
    },
    'php': {
        image: '',
        cmd: ['']
    },
}

function twoSum(nums: number[], target: number): number[] {
    const map = new Map();
    for(let i = 0; i < nums.length; i++) {
        if(map.has(target - nums[i])) {
            return [map.get(target - nums[i]), i];
        } else {
            map.set(nums[i], i);
        }
    }
    return []
}

console.log(twoSum([1, 2, 3, 4, 5], 3))

import React, { useEffect, useRef, useState } from 'react';
import * as d3 from 'd3';

export default function useD3(renderChartFn : (svg : d3.Selection<SVGElement,{},HTMLElement>) => any, dependencies : any[]) {
    const ref = useRef<SVGSVGElement>();

    useEffect(() => {
      let d3El = d3.select(ref.current)
        renderChartFn(d3.select(ref.current));
        return () => {};
      }, dependencies);
    return ref;
}

function MyChart(props : {
    w: number,
    h: number,
    data: Array<any>
}) {
    const [currentData,setCurrentData] = useState(props.data)

    let svgRef = useD3((svg) => {
        if (props.data === currentData) return
        setCurrentData(props.data)
        // add d3 code
        svg.selectAll("*").remove();

        const margin = { top: 0, right: 80, bottom: 20, left: 10 };

        const width = props.w - margin.left - margin.right;
        const height = props.h - margin.top - margin.bottom;

        const canvas = svg
            .attr('width', width + margin.left + margin.right)
            .attr('height', height + margin.top + margin.bottom)
            .append('g')
            .attr('transform', `translate(${margin.left},${margin.top})`);

        // data

        const data = props.data
    },[props])

    return (<svg ref={svgRef} />)
}

//Retries maxRetries number of times, meaning that if you have 0, then it'll run the function once.
async function retryPromise<T>(
  promiseFn: () => Promise<T>, 
  maxRetries = 3, 
  delayOffset = 0, 
  delayRandomRange = 0
): Promise<T> {

  return new Promise<T>((resolve, reject) => {
    promiseFn()
      .then(resolve, (error: any) => { //On error
        if (maxRetries <= 0) {
          return reject(error);
        } else {
          if(delayRandomRange * Math.random() + delayOffset < 1.0){
            return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolve, reject);
          }else{
            return new Promise<T>((resolveTwo, rejectTwo) => {
              setTimeout(() => {
                return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolveTwo, rejectTwo);
              }, delayRandomRange * Math.random() + delayOffset);
            }).then(resolve, reject);
          }
        }
      });
  });
}

//Returns a function that will fail numTimes times, then will return aValue
function functionThatReturnsAFunctionThatFailsACoupleTimes(numTimes: number, aValue: any): () => Promise<any> {
  return async function(){
    if(numTimes == 0){
      return aValue;
    }
    numTimes--;
    throw false;
  };
}

const SMALL_NUMBER = 10;

function testTest(failNumberOfTimes: number){

  let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(failNumberOfTimes, true);

  //Test my test
  for(let i = 0; i < (failNumberOfTimes * 2); ++i){
    function evalTest(val: any){
      let testTestFailedReason = "";
      if(val === undefined){
        testTestFailedReason = "Test test returned undefined for some reason.";
      }
      if((i + 1) > failNumberOfTimes){
        if(val === true){
          //We're good
        }else{
          testTestFailedReason = "Test test didn't return true when it should have.";
        }
      }else{
        if(val === false){
          //We're good
        }else{
          testTestFailedReason = "Test test didn't return false when it should have.";
        }
      }
      testTestFailedReason = testTestFailedReason || "Test test passed test case";
      console.log(testTestFailedReason, "at index", i, "where the function returned", val);
    }
    functionThatFailsACoupleTimes().then(evalTest, evalTest)
  };
}

testTest(SMALL_NUMBER);

let testCaseCounter = 1;

const throwsNoError = [
  (val: any) => {
    if(val == true){
      console.log("Passed test case " + testCaseCounter++);
    }else{
      console.error("Unexpected return value", val);
    }
  },
  () => {
    console.error("It wasn't supposed to fail!")
  }
]

const throwsError = [
  (val: any) => {
    console.error("It wasn't supposed to succeed!", val);
  },
  (val: any) => {
    if(val == false){
      console.log("Passed test case " + testCaseCounter++);
    }else{
      console.error("Unexpected return value", val);
    }
  }
];

//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first one
let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1).then(...throwsNoError)

functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2).then(...throwsError)

//Testing the delay. You'll have to wait a bit too.

functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1, 500, 500).then(...throwsNoError)

functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);

//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2, 500, 500).then(...throwsError)

class DFS
{
   public dfs(G: DFSGraph, startVert: number)
   {
       let visited: boolean[] = Array<boolean>();
       // Pre-populate array:
       for(let i = 0; i < G.size; i++)
       {
           visited.push(false);
       }

       let s: number[] = new Array();

       visited[startVert] = true;

       s.push(startVert);

       while(s.length > 0)
       {
           const v = s.pop();
           for(let adjV of G.adj[v])
           {
               if(!visited[adjV])
               {
                   visited[adjV] = true;
                   s.push(adjV);
               }
           }
       }
   }

   public dfsRecursive(G: DFSGraph, startVert: number)
   {
       let visited: boolean[] = Array<boolean>();
       // Pre-populate array:
       for(let i = 0; i < G.size; i++)
       {
           visited.push(false);
       }
       this.dfsAux(G, startVert, visited);
   }

   private dfsAux(G: DFSGraph, v: number, visited: boolean[])
   {
       visited[v] = true;
       for(let adjV of G.adj[v])
       {
           if(!visited[adjV])
           {
               // this.foo(); // Something can happen before the visit.
               this.dfsAux(G, adjV, visited);
               // this.bar(); // Something can happen after the visit.
           }
       }
   }
}

class DFS
{
   public dfs(G: DFSGraph, startVert: number)
   {
       let visited: boolean[] = Array<boolean>();
       // Pre-populate array:
       for(let i = 0; i < G.size; i++)
       {
           visited.push(false);
       }

       let s: number[] = new Array();

       visited[startVert] = true;

       s.push(startVert);

       while(s.length > 0)
       {
           const v = s.pop();
           for(let adjV of G.adj[v])
           {
               if(!visited[adjV])
               {
                   visited[adjV] = true;
                   s.push(adjV);
               }
           }
       }
   }

   public dfsRecursive(G: DFSGraph, startVert: number)
   {
       let visited: boolean[] = Array<boolean>();
       // Pre-populate array:
       for(let i = 0; i < G.size; i++)
       {
           visited.push(false);
       }
       this.dfsAux(G, startVert, visited);
   }

   private dfsAux(G: DFSGraph, v: number, visited: boolean[])
   {
       visited[v] = true;
       for(let adjV of G.adj[v])
       {
           if(!visited[adjV])
           {
               // this.foo(); // Something can happen before the visit.
               this.dfsAux(G, adjV, visited);
               // this.bar(); // Something can happen after the visit.
           }
       }
   }
}