This task can be soved using a linear Frederickson shortest path algo.

I thought my algo is all right but got wa3&5.
Why?
Because I saw this in the statement: rounded to the integer
So,I wrote printf("%.0lf",a+0.49999999);
But it seemed to be wrong.
I checked again and again,finally I found the problem:
When you use %x.ylf,where x and y are numbers,the result is automatically rounded.
However,when using (int)a,it means FLOOR.
So,if you want to write rounded ans,there are 2 ways:
    printf("%d",(int)(a+0.499999999));
or  printf("%.0lf",a);

How did you do that http://acm.timus.ru/status.aspx?space=1&num=1220&status=accepted&from=2371261&count=2 ???!  8-()

I have isolated the trees at first, then i ran a topsort.
I dont understand why i get WA #8

Please tell me why this program give WA on test8, thanks!
#include <iostream>
using namespace std;
void main()
{
    int sum=0;
    char s[1000];
    first:
    while(cin.getline(s,1000))
    {
        for(int i=0;i<strlen(s);i++)
        {
            switch(s[i])
            {
                case'a':case'd':case'g':case'j':case'm':case'p':case's':case'v':case'y':case'.':case' ':
                    sum+=1;
                    break;
                case'b':case'e':case'h':case'k':case'n':case'q':case't':case'w':case'z':case',':
                    sum+=2;
                    break;
                case'c':case'f':case'i':case'l':case'o':case'r':case'u':case'x':case'!':
                    sum+=3;
                    break;
            }
        }
    }
    cout<<sum;
}

The path is a circle.

В двух местах "число не превышающие 35" следует заменить на "число, не превышающее 35".

I can't understand what's wrang? I just build BST and make reverse post order..
Maybe there are some troubles with input?
Please help me. [I'll delete code after receiving some feedback]

[Code deleted]

Edited by author 29.11.2012 21:04

Если взглянуть на Рейтинг решения задач,  и пройтись по столбику "Выделено памяти", то у ребят из ТОПа выделено 18, 38, 74, 78кб памяти. Но как, как, как возможен такой маленький расход памяти, там же реально меньше 300 кб не добиться, ну никак! В чем же тут загадка???

Should it be geometry or physics ???

I've found that test #1 is the same as sample. I've special-cased it in my program to output exactly what is in the sample output, but I still get WA1. Why?

Looks like it depends on language: C and Java program output exactly the same, but C program passes the test, and Java program doesn't.

Edited by author 03.08.2011 00:41

#include<stdio.h>
#include<conio.h>
int main()
{
    int a, sum = 0;
scanf("%d",&a);
    if( a > 0 )
    {
        for ( int i = -1; i <= a; i++)
        sum += i;
    }

    else
    {
        for (int i = 1; i <= -a; i++)
        sum += i;
        sum = 1 - sum;
    }
printf("summa ravna %d",sum);
getch();
}

#include <stdio.h>
#include <math.h>
long long int k,n;
void reverce (void);
int main(void)
{
  reverce();
  return 0;

}

void reverce (void)
{
    long long int a;
    while(scanf("%lld", &a))
      {
        k++;
        n++;
        reverce();
      }
    if (k == n)
      {
         n--;
         return;
      }
    printf("%.4lf\n", (double)sqrt(a));
}

Edited by author 29.11.2012 01:43

I use dijkstra algo, what's wrong?
code



#include <cstdio>
#include <vector>
#include <map>
#include <set>
using namespace std;
const long long INF=100000000;
typedef unsigned long long ULL;
typedef pair<long long,long long> pii;
typedef vector<vector<long long> > VVI;
typedef vector<long long> vi;
typedef map<long long,vi> MIV;
MIV network;
VVI G;

long long n=1,n_int;
void init_vert(){
        for (long long i=0;i<=n;++i){
                vector< long long > temp;
                G.push_back(temp);
            }
        for (MIV::iterator it=network.begin();it!=network.end();++it){
            for(vi::iterator vit=it->second.begin();vit!=it->second.end();++vit){
                for(vi::iterator vit2=it->second.begin();vit2!=it->second.end();++vit2){
                    G[*vit].push_back(*vit2);
                }
            }
        }
    }

long long read_network(){
    long long res=0;
    long long mask=0;
    long r1,r2,r3,r4;
    long m1,m2,m3,m4;
    scanf("%ld.%ld.%ld.%ld",&r1,&r2,&r3,&r4);
    scanf("%ld.%ld.%ld.%ld",&m1,&m2,&m3,&m4);

    res+=r1&m1;res<<8;
    res+=r2&m2;res<<8;
    res+=r3&m3;res<<8;
    res+=r4&m4;

        return res;
    }


vector<long long> dist,parent;


void dejkstra(long long s){
    dist.assign(n+1,INF);
    parent.assign(n+1,INF);
    dist[s]=0;
    set<pair<long long,long long>  > q;
    q.insert(make_pair(dist[s],s));
    while (!q.empty()){
            long long v=q.begin()->second;
            q.erase(q.begin());
            for (size_t j=0;j<G[v].size();++j){
                    long long to=G[v][j];
                    if (dist[v]+1<dist[to]){
                            q.erase(make_pair(dist[to],to));
                            dist[to]=dist[v]+1;
                            parent[to]=v;
                            q.insert(make_pair(dist[to],to));
                        }
                }
        }
    }

int main(){
        //freopen("in","r",stdin);
        scanf("%lld",&n);
        long long n_n_m=0;
        for (size_t i=0;i<n;++i){
            scanf("%lld",&n_int);
            for (size_t j=0;j<n_int;++j){
                n_n_m=read_network();
                network[n_n_m].push_back(i+1);
            }
        }
        init_vert();
        long long _beg,_end;
        scanf("%lld%lld",&_beg,&_end);
        dejkstra(_beg);


        if (dist[_end]==INF){
                printf("No\n");
                return 0;
            }
        else{
                printf("Yes\n");
                long long p=_end;
                vector<long long>res;
                printf("%lld ",_beg);

                while(p!=_beg){
//                        printf(">>>%d\n",p);
                        res.push_back(p);
                        p=parent[p];


                    }
                 for (vi::reverse_iterator it=res.rbegin();it!=res.rend();++it){
                        printf("%lld ",*it);
                    }

                printf("\n");
            }
        return 0;
    }

Please send me.

var a,b,n,k:integer;
begin
readln(n,k);
a:=n div 2;
if k>a then b:=n-k
       else if (k=a) or (k=a+1) then b:=0
                                else b:=a-k;
writeln(b)
end.

Right... I guess this problem was put in here for comic relief. :)

For crying out loud, the author didn't even bother to increase the limits so as to make this a 'bignum' problem... :P

У меня программа получила AC, хотя на тест 1999 выдавала ответ 1991... мне кажется, что это не совсем верно...