#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    int a, sum = 0;
    cin >> a;

    if( a > 0 )
    {
        for ( int i = 1; i <= a; i++)
        sum += i;
    }

    else
    {
        for (int i = 1; i <= abs(a); i++)
        sum += i;
        sum = 1 - sum;
    }

    cout << sum;
    return 0;
}

#include <iostream>
#include <cstring>
#include <algorithm>
using namespace std;

struct Date
{
    int day;

    int month;

    int year;
};

struct person
{
    int num;

    int live;

    Date die;
};

bool comp(person a, person b)
{
    if (a.live != b.live) return a.live > b.live;
    if (a.die.year != b.die.year) return a.die.year < b.die.year;
    if (a.die.month != b.die.month) return a.die.month < b.die.month;
    if (a.die.day != b.die.day) return a.die.day < b.die.day;
}

bool leap(int year)
{
    if (year%400==0) return 1;
    if (year%100==0) return 0;
    if (year%4==0) return 1;
    else return 0;
}

int monthDay(int year, int month)
{
    if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) return 31;

    else if (month == 4 || month == 6|| month == 9 || month == 11) return 30;

    else if (leap(year))return 29;

    else return 28;
}

int Distance(Date a, Date b)//a??¨®¨²b  o??e¨º?¨®????1¨¨??¨²
{
    int dis = 0;

    for (int i = a.year+1; i < b.year; ++i)
    {
        if (leap(i)) dis += 366;

        else dis += 365;
    }

    if (a.year != b.year)
    {
        for (int i = a.month+1; i <= 12; ++i)
        {
            dis += monthDay(a.year, i);
        }

        dis += (monthDay(a.year, a.month) - a.day + 1);

        for (int i = 1; i < b.month; ++i)
        {
            dis += monthDay(b.year, i);
        }

        dis += b.day;
    }
    else
    {
        if (a.month != b.month)
        {
            dis += (monthDay(a.year, a.month) - a.day + 1);cout << monthDay(a.year, a.month) << endl;

            for (int i = a.month+1; i < b.month; ++i)
            {
                dis += monthDay(b.year, i);
            }

            dis += b.day;
        }
        else
        {
            dis += (b.day - a.day + 1);
        }
    }

    return dis;
}

int convert(char a, char b)
{
    return (a - '0')*10 + b - '0';
}

int convert(char a, char b, char c, char d)
{
    return (a - '0')*1000 + (b - '0')*100 + (c - '0')*10 + d - '0';
}

void print(Date a)
{
    cout << a.year << " " << a.month << " " << a.day << endl;
}

int main()
{
    int m;

    cin >> m;

    char useless[11];

    Date a, b;

    person p[101];

    for (int i = 0; i < m; ++i)
    {
        scanf("%d.%d.%d", &a.day, &a.month, &a.year);

        cin >> useless;

        scanf("%d.%d.%d", &b.day, &b.month, &b.year);

        p[i].num = i+1;

        p[i].live = Distance(a, b);

        p[i].die = b;
    }

    sort(p, p+m, comp);

    cout << p[0].num << endl;

    system("pause");
}

Time limit decreased from 1 second to 0.5 second (it corresponds better to the original TL in 2004). The problem was rejudged. Many old solutions with TLE verdict got AC, while all new solutions working in time from 0.5 to 1 second got TLE.

      n , k
1. if ( n = 0 ) , then answer = ( 1 ).
2. if ( n = 1 ) , then answer = ( k-1 ).
3. else answer(n) = ( k-1 ) * ( answer(n-1,k) + answer(n-2,k) ).

Edited by author 20.06.2010 04:04

http://acm.timus.ru/rating.aspx?space=1&num=1001&lang=cpp

How to do with 0.015s and 369Kb??

не понимаю

There are a lot of tests (i know two: 4 and 9), in which r <= 0. Please, change it!

I do not understand what is wrong with my code it works ok on my PC:

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in, "ISO-8859-1"));
        char[] buffer = new char[262144];
        br.read(buffer);
        Scanner in = new Scanner(new String(buffer));
        Stack<String> lifo = new Stack<String>();
        DecimalFormat format = new DecimalFormat("0.00000", new DecimalFormatSymbols(Locale.US));
        while (in.hasNextLong()) {
            lifo.push(format.format(Math.sqrt(in.nextLong())));
        }
        while(!lifo.empty()){
            System.out.println(lifo.pop());
        }
    }

Could someone explain it to me ?

1: be careful of float point...
2: if there are K guys paid more than they drinked, the answer shouldn't be 100.0 / k, you should consider how much they paid...

I use bs + MST(Prim), please help me!!! Here is my code:

#include <iostream>
#include <iomanip>
#include <algorithm>
#include <cstring>
#include <cstdio>
#include <vector>
#define MAXN 1005
#define MAXE 500005
#define oo 1e100
#define EPS 1e-9
#define nabs(x) ((x) < 0? -(x) : (x))
using namespace std;
struct edge {
    int to, l, c, back;
    edge() {
    }
    edge(int _to, int _l, int _c, int _back) {
        to = _to;
        l = _l;
        c = _c;
        back = _back;
    }
} E[MAXE + MAXE];

int n, m, ce;
int ptr[MAXN];
long double d[MAXN];
bool mark[MAXN];

void add_edge(int a, int b, int l, int c) {
    E[ce] = edge(b, l, c, ptr[a]);
    ptr[a] = ce++;
    E[ce] = edge(a, l, c, ptr[b]);
    ptr[b] = ce++;
}
long double Prim(long double x) {
    for (int i = 1; i < n + 1; i++)
        d[i] = oo;
    d[1] = 0;

    long double res = 0, _min, val;
    int v, w;
    memset(mark, 0, sizeof(mark));
    for (int pass = 0; pass < n; pass++) {
        _min = oo;
        for (int i = 1; i < n + 1; i++)
            if (!mark[i] && d[i] < _min) {
                v = i;
                _min = d[i];
            }

        mark[v] = true;
        res += _min;

        for (int i = ptr[v]; i != -1; i = E[i].back) {
            w = E[i].to;
            val = E[i].c - x * E[i].l;
            d[w] = min(d[w], val);
        }
    }

    return res;
}
int main() {
    int a, b, l, c;
    memset(ptr, -1, sizeof(ptr));
    scanf("%d%d", &n, &m);
    while (m--) {
        scanf("%d%d%d%d", &a, &b, &l, &c);
        add_edge(a, b, l, c);
    }

    if(n == 1){
        cout << "0" << endl;
        return 0;
    }

    long double lo = 0, hi = 1e15, mit, fmit, flo;
    for (; nabs(hi - lo) > EPS;) {
        mit = (lo + hi) / 2;
        fmit = Prim(mit);
        flo = Prim(lo);
        if (flo * fmit < 0)
            hi = mit;
        else
            lo = mit;
    }


    cout << setprecision(8) << lo << endl;

}

No 1585
VAR pingvins:String; n,a,b,c,i:Integer;
begin
  Readln(n);
  a:=0; b:=0; c:=0;
  FOR i:=1 TO n DO
  begin
    Readln(pingvins);
    Case pingvins OF
     'Emperor Penguin' : a:=a+1;
     'Little Penguin' : b:=b+1;
     'Macaroni Penguin' : c:=c+1;
    end;
  end;
  IF (a>b) and (a>c) THEN Writeln('Emperor Penguin');
  IF (b>a) and (b>c) THEN Writeln('Little Penguin');
  IF (c>a) and (c>b) THEN Writeln('Macaroni Penguin');
end.

Where is problem?

#include<iostream>
#include<map>
using namespace std;
int main()
{
    map<int,int>a;
    int n,k,i,m,l,p=0;
    cin>>n;
    for(i=0;i<n;i++)
    {
    cin>>k; a[k]++;
    }

    cin>>m;
    for(i=0;i<m;i++)
    {
    cin>>k; a[k]++;
    }

    cin>>l;
    for(i=0;i<l;i++)
    {
    cin>>k; a[k]++;
    if(a[k]==3){p++;}
    }


    cout<<p;

    //system("pause");
    return 0;}

#include <iostream>
#include <cstdio>

using namespace std;

int main()
{
    int N;
    double sum;
    scanf("%d", &N);
    for(int i = 0; i < N; i++)
    {
        int p;
        scanf("%d", &p);
        sum += (double)p;
    }
    sum /= double(N);
    printf("%.6lf", sum);
    return 0;
}

Here is my code:

#include <iostream>

using namespace std;

int x[200];

int compare (const void *a, const void *b)
{
    return (*(int*)a - *(int*)b);
}

int main()
{
    int r[200], a = 3;
    long min;
    bool z = false;
    for (int  i = 0; i<3; i++)
        cin>>x[i];
    for ( ; ; )
    {
        qsort (x, a, sizeof(int), compare);
        min = 1000000000;
        for (int i = 0; i<a-1; i++)
        {
            r[i] = abs(x[i] - x[i+1]);
            if (r[i]<min)
                min = r[i];
        }
        x[a] = min;
        for (int j = 0; j<a; j++)
        {
            if (x[j] == min)
            {
                z = true;
                break;
            }
        }
        if (z == true) break;
        a++;
    }
    printf("%d", a - 1);
    return 0;
}

Where is my mistake?

" It is a tradition that a subordinate's computer has number that is greater than the number of his commander's computer. Each military person"  why there are some ki > i ? in th 9th case, isn't it a tree with the root 1?

What is special in test # 4?
I tried all examples on the webboard and my program gives the correct result.


Edited by author 28.09.2012 15:13

input->1
output->1

I'm received WA1 using standart bubble-sort (without saving original order). My answer for  example task is correct (at least my solution coverred task conditions):

ex. answer | my answer
3 5        |3 5
26 4       |22 4
22 4       |26 4
16 3       |20 3
20 3       |16 3
1 2        |11 2
11 2       |1 2
7 1        |7 1

In example task sorted array has saved original order. Maybe it cause wrong answer 1?
At that case this important condition must be set in task.

I think my program is correct. Who can tell me why I got wa?

#include<cstdio>
#include<cstdlib>
#include<cstring>
char a[100005],b[100000];
char cs[]="=+-*/0123456789)(";
bool pd(char ch){
    for(int i=0;i<17;i++)
       if(ch==cs[i]) return 1;
    return 0;
}

int main(){
    while(gets(b)){
       strcat(a,b);
    }
    int len=strlen(a);
    int ha=0,k=0;
    for(int i=0;i<len;i++){
         if(ha){
            if(a[i]=='*' && a[i+1]==')')
                ha=0;
         }else{
            if(a[i]=='*' && a[i-1]=='(')
                ha=1;
            else{
                if(k>0 && (!pd(a[i]))){ printf("NO"); return 0; }
                if(a[i]=='(') k++;
                if(a[i]==')') k--;
                if(k<0) { printf("NO"); return 0;}
            }
         }
    }
    if(ha || k!=0) { printf("NO"); return 0; }
    else printf("YES");
    system("pause");
    return 0;
}