Codeforces rating Estimater

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;
import java.net.URL;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Scanner;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonObject;

public class codeforcesAPI {
    public static void main(String[] args) throws IOException, NoSuchAlgorithmException {
        Scanner scan = new Scanner(System.in);
        String handle = scan.nextLine();

        listContest(handle);

    }

    public static void listContest(String user) throws IOException {
        UserContestRatingHistory hist = getUserContestRatingHistory(user);
        for(contest g : hist.result){
            System.out.print("Finding Personal Seed: ");
            int[] f = seed(user, g.contestId);
            int mean = (int)Math.sqrt(f[0] * f[2]);
            System.out.println("[Done]");

            System.out.print("Finding All Seeds: ");
            UserContestRatingChange a = getUserContestRatingChange(g.contestId);
            seedRankRating[] seeds = new seedRankRating[a.result.length];
            int myRate = 0;
            int myNew = 0;
            for(int i = 0;i<a.result.length;i++){
                String handle = a.result[i].handle;
                if(handle.equalsIgnoreCase(user)) {
                    myRate = a.result[i].oldRating;
                    myNew = a.result[i].newRating;
                }
                int[] q = seed2(handle, g.contestId, a);
                int curSeed = q[0];
                seeds[i] = new seedRankRating(curSeed, a.result[i].rank, a.result[i].oldRating);
                if(i != 0) System.out.print("\b".repeat(((i) +"/"+a.result.length).length() + 2));
                System.out.print("[" + (i+1) +"/"+a.result.length + "]");
            }
            System.out.print("\b".repeat((a.result.length + "").length()*2 + 3));
            Arrays.sort(seeds);
            int index = Arrays.binarySearch(seeds, new seedRankRating(mean, 1, 1));
            if(index< 0) index = -(index+1);
            int rating = seeds[index].rating;
            int average = (rating + myRate)/2;
            System.out.println("[Done]");


            System.out.print("[" + g.contestName + "    " + g.contestId + "]:" + " ".repeat(Math.max(65 - g.contestName.length(), 10)));
            System.out.println("Total: " + f[1] + "      Expected: " + f[0] + "     Got: " + f[2] + "     RateGuess: " + average + "   Actual: " + myNew);
        }
    }

    public static int[] seed(String name, int id) throws IOException {
        UserContestRatingChange a = getUserContestRatingChange(id);
        int myRate = 0;
        int myRank = 0;
        for(contest g : a.result){
            if(g.handle.equalsIgnoreCase(name)){
                myRate = g.oldRating;
                myRank = g.rank;
                break;
            }
        }
        double curSeed = 0;
        for(contest g : a.result){
            if(g.oldRating > myRate){
                curSeed += elo(g.oldRating, myRate);
            }
        }
        return new int[] {(int)curSeed, a.result.length, myRank};
    }

    public static int[] seed2(String name, int id, UserContestRatingChange a) throws IOException {
        int myRate = 0;
        int myRank = 0;
        for(contest g : a.result){
            if(g.handle.equalsIgnoreCase(name)){
                myRate = g.oldRating;
                myRank = g.rank;
                break;
            }
        }
        double curSeed = 0;
        for(contest g : a.result){
            if(g.oldRating > myRate){
                curSeed += elo(g.oldRating, myRate);
            }
        }
        return new int[] {(int)curSeed, a.result.length, myRank};
    }

    public static UserContestRatingChange getUserContestRatingChange(int id) throws IOException {
        URL oracle = new URL("https://codeforces.com/api/contest.ratingChanges?contestId=" + id);
        BufferedReader in = new BufferedReader(new InputStreamReader(oracle.openStream()));
        String inputLine;
        String tot = "";
        while ((inputLine = in.readLine()) != null) tot += inputLine;

        JsonObject s = new Gson().fromJson(tot, JsonObject.class);
        Gson gson = new GsonBuilder().setPrettyPrinting().create();
        String prettyJson = gson.toJson(s);
        UserContestRatingChange o = gson.fromJson(prettyJson, UserContestRatingChange.class);
        return o;
    }

    public static UserContestRatingHistory getUserContestRatingHistory(String user) throws IOException {
        URL oracle = new URL("https://codeforces.com/api/user.rating?handle=" + user);
        BufferedReader in = new BufferedReader(new InputStreamReader(oracle.openStream()));
        String inputLine;
        String tot = "";
        while ((inputLine = in.readLine()) != null) tot += inputLine;

        JsonObject s = new Gson().fromJson(tot, JsonObject.class);
        Gson gson = new GsonBuilder().setPrettyPrinting().create();
        String prettyJson = gson.toJson(s);
        UserContestRatingHistory o = gson.fromJson(prettyJson, UserContestRatingHistory.class);
        return o;
    }

    public static int getUserRating(String user) throws IOException {
        UserContestRatingHistory f = getUserContestRatingHistory(user);
        return f.result[f.result.length-1].newRating;
    }

    public static double elo(int a, int b) {

        double elo = 1/(1 + 10*(((double)a - (double)b)/400));
        if(elo < 0) return -1;
        return (1 - elo);
    }


    public class UserContestRatingHistory {
        String status;
        contest[] result;

        public UserContestRatingHistory(String status, contest[] result) {
            this.status = status;
            this.result = result;
        }

        @Override
        public String toString() {
            return "out{" +
                    "status='" + status + '\'' +
                    ", result=" + Arrays.toString(result) +
                    '}';
        }
    }

    public class UserContestRatingChange {
        String status;
        contest[] result;

        public UserContestRatingChange(String status, contest[] result) {
            this.status = status;
            this.result = result;
        }

        @Override
        public String toString() {
            return "out{" +
                    "status='" + status + '\'' +
                    ", result=" + Arrays.toString(result) +
                    '}';
        }
    }

    public class contest{
        int contestId;
        String contestName;
        String handle;
        int rank;
        long ratingUpdateTimeSeconds;
        int oldRating;
        int newRating;

        public contest(int contestId, String contestName, String handle, int rank, long ratingUpdateTimeSeconds, int oldRating, int newRating) {
            this.contestId = contestId;
            this.contestName = contestName;
            this.handle = handle;
            this.rank = rank;
            this.ratingUpdateTimeSeconds = ratingUpdateTimeSeconds;
            this.oldRating = oldRating;
            this.newRating = newRating;
        }

        @Override
        public String toString() {
            return "obj{" +
                    "contestId=" + contestId +
                    ", contestName='" + contestName + '\'' +
                    ", handle='" + handle + '\'' +
                    ", rank=" + rank +
                    ", ratingUpdateTimeSeconds=" + ratingUpdateTimeSeconds +
                    ", oldRating=" + oldRating +
                    ", newRating=" + newRating +
                    '}';
        }
    }

    public static class seedRankRating implements Comparable<seedRankRating>{
        int seed;
        int rank;
        int rating;

        public seedRankRating(int seed, int rank, int rating) {
            this.seed = seed;
            this.rank = rank;
            this.rating = rating;
        }


        @Override
        public int compareTo(seedRankRating o) {
            return this.seed - o.seed;
        }
    }

}