I`m sure that written algo is correct, but I might make stupid mistake...
My solutions can pass all my tests and my friends` also.

Please, give me some tricky tests!

Thanks a lot!

I keep getting non-zero return from WA #9 (meaning some of my scanf() fails)
Could you please forward WA #9 problem so that I can check parsing is proper?
Thank you,

import java.io.*;
import java.util.*;

public class task {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        int n = in.nextInt();
        int k = in.nextInt();
        int t;

        if(n>=1 && k<=1000) {
            if((int) (n * 2.0 / k) == (n * 2.0 / k)) t = (int) (n * 2.0 / k);
            else t = 1 + (int) (n * 2.0 / k);
            out.print(t);

        }
        out.flush();
   }
}

#include <iostream>
#include <stdio.h>
#include <vector>

using namespace std;

class Place {
public:
    char x;
    int y;

    bool isOnboard() {
        if (x < 'a' || x > 'h' || y < 1 || y > 8) return false;
        return true;
    }



    Place(char x, int y) {
        this->x = x;
        this->y = y;
    }

};



int main(int argc, const char * argv[])
{
    int N;
    cin >> N;


    vector<Place> places;

    for (int i = 0; i < N; i++) {
        char x;
        int y;
        cin.get(x);

        if (x == '\n') {
            i--;
            continue;
        }

        cin >> y;

        Place place (x, y);
        places.push_back(place);

    }


    for (int i = 0; i < N; i++) {
        Place place = places[i];
        int moves = 0;


        //left 2 up 1
        place.x -= 2;
        place.y -= 1;
        moves += place.isOnboard();

        //left 2 down 1
        place.y += 2;
        moves += place.isOnboard();

        //right 2 down 1
        place.x += 4;
        moves += place.isOnboard();
        //right 2 up 1
        place.y -= 2;
        moves += place.isOnboard();

        //right 1 up 2
        place.x -= 1;
        place.y -= 1;
        moves += place.isOnboard();

        //left 1 up 2
        place.x -= 2;
        moves += place.isOnboard();

        //left 1 down 2
        place.y += 4;
        moves += place.isOnboard();

        //right 1 down 2
        place.x += 2;
        moves += place.isOnboard();

        cout << moves << endl;

    }



}

I get, Runtime error (non-zero exit code), even if I send a program such:

fn main() {
    println!("{}",-1);
}

Когда использую циклы такого вида выдает ошибку Runtime error (non-zero exit code)

i=n;
while(i>0) {
    name[i]=calloc(1,30);
    scanf(" %s",name[i]);
    i--;
}
i=n;
while(i>0) {
    char *buf=name[i];
    while(*buf!='\0') {
        if(*buf=='+') {
            kol++;
            break;
        } else {
            buf++;
        }
    }
    i--;
}

А здесь AC
for(i=0;i<n;i++) {
    name[i]=calloc(1,30);
    scanf(" %s",name[i]);
}
for(i=0;i<n;i++) {
    char *buf=name[i];
    while(*buf!='\0') {
        if(*buf=='+') {
            kol++;
            break;
        } else {
            buf++;
        }
    }
}

try
6
6 0
3 0
5 0
5 6 0
0
0

and

7
2 0
5 0
6 4 0
5 7 0
0
0
0

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.*;

public class Lesson {

    public static void main(String[] args) throws Exception {

        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        int countPrepod = Integer.parseInt(bufferedReader.readLine());
        TreeSet<Long> prepod = new TreeSet();
        for (int i = 0; i < countPrepod; ++i) {
            prepod.add(Long.parseLong(bufferedReader.readLine()));
        }

        int countStudent = Integer.parseInt(bufferedReader.readLine());
        ArrayList<Long> student = new ArrayList();
        for (int i = 0; i < countStudent; ++i) {
            student.add(Long.parseLong(bufferedReader.readLine()));
        }

        student.sort(((o1, o2) -> Long.compare(o1,o2)));
        int result=0;
        for (long find:prepod)
        {
                while (Collections.binarySearch(student,find)>=0)
                {
                    ++result;
                    student.remove(find);
                }
        }
        System.out.println(result);
    }

}

1. This problem can be reduced to the following:
      Given X, find two vertices such that path weight is equal to X.
2. It probably cannot be solved with naiive DP. Use centroid decomposition.
3. std::unordered_map gets TL while std::map gets AC.

i have some problems with (), please give answers for some other cases

What it is it? My program overcome all my tests,but system(TIMUS) written me about WA#9!
 WHY?

Don't be afraid of geometry, this problem is really easy

Can you help me?

#include<iostream>

using namespace std;
int sum(int temp);
int main(){
    int a[6];
    scanf("%1d%1d%1d%1d%1d%1d",&a[0],&a[1],&a[2],&a[3],&a[4],&a[5]);
    int first=a[0]*100+a[1]*10+a[2];
    int second=a[3]*100+a[4]*10+a[5];
    if(a[3]==9&&a[4]==9&&a[5]==9){
        cout<<"No";
        return 0;
    }
    int pre=second-1;
    int next=second+1;
    if((sum(pre)==(a[0]+a[1]+a[2]))||(sum(next)==(a[0]+a[1]+a[2]))){
        cout<<"Yes";
    }else{
        cout<<"No";
    }

return 0;
}

int sum(int temp){
    int count=0;
    do{
        count+=(temp%10);
        temp/=10;
    }while(temp/10!=0);
    count+=temp;
    return count;
}

#include<iostream>
#include<vector>
#include<string>
#include<algorithm>
using namespace std;

class team{
    public:
        string id;
        int n;
};

bool comp(const team &t1,const team &t2);

int main(){
    int k;
    cin>>k;
    vector<team> T;
    while(k--){
        string temp;
        int num;
        cin>>temp>>num;
        team t;
        t.id=temp;
        t.n=num;
        T.push_back(t);
    }
    stable_sort(T.begin(),T.end(),comp);
    for(int i=0;i<T.size();++i){
        cout<<T[i].id<<" "<<T[i].n<<endl;
    }

return 0;
}

bool comp(const team &t1,const team &t2){
    return t1.n>t2.n;
}

Why Wring answer?
import java.util.Scanner;

public class T1654 {
    public static char[] arr;
    public static String out = "";
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner sc = new Scanner(System.in);
        String inp = sc.next();
        sc.close();
        arr = new char[inp.length()];
        arr = inp.toCharArray();
        format();
        if(out != "") {
            System.out.println(out);
        } else {
            System.out.println("");
        }

    }

    public static void format() {
        boolean isFormat = false;
        int l = arr.length;
        for(int i = 0; i< l-1; i++) {
            if(arr[i] == arr[i+1]) {
                arr[i] = 0;
                arr[i+1] = 0;
                isFormat = true;
                } else if(arr[i] != arr[i+1] & arr[i] != 0){
                out += arr[i];
            }
        }
        out+= arr[arr.length-1];
        if(isFormat == true) {
            arr = new char[out.length()];
            arr = out.toCharArray();
            out = "";
            format();
        }
    }

}

получил АС, долго искал где долбанный баг, т.к. ТЕСТ 22 выдавал ошибку по времени, если у вас такая же проблема и вы используете преобразование double в int то в 22 тесте точность P и Q 3 знака, поэтому ТЛ и выдает, вероятно на вход подаются какие нибудь числа 22.333 и 22.334
удачи

code like:

size_t out = 0;
printf ("%zu\n", out);

result - > wa#1 (((

if i use

printf ("%d\n", out);

all  test accepted (( Why?
https://wandbox.org/ & gcc 7.1  - The first version works correctly (((

i have ac in 0.187 s, but on this test my program runs at least 0.9:

35 123
2 3 4 5 6 0 8 9 10 11 0 13 14 15 0 17 18 0 20 21 0 23 0 25 0 27 0 0 0 0 0 0 0 0 0