Codeforces Round #443 (Div. 2)

A. Borya's Diagnosis
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

It seems that Borya is seriously sick. He is going visit n doctors to find out the exact diagnosis. Each of the doctors needs the information about all previous visits, so Borya has to visit them in the prescribed order (i.e. Borya should first visit doctor 1, then doctor 2, then doctor 3and so on). Borya will get the information about his health from the last doctor.

Doctors have a strange working schedule. The doctor i goes to work on the si-th day and works every di day. So, he works on days si, si + di, si + 2di, ....

The doctor's appointment takes quite a long time, so Borya can not see more than one doctor per day. What is the minimum time he needs to visit all doctors?

Input

First line contains an integer n — number of doctors (1 ≤ n ≤ 1000).

Next n lines contain two numbers si and di (1 ≤ si, di ≤ 1000).

Output

Output a single integer — the minimum day at which Borya can visit the last doctor.

Examples
input
3
2 2
1 2
2 2
output
4
input
2
10 1
6 5
output
11
Note

In the first sample case, Borya can visit all doctors on days 2, 3 and 4.

In the second sample case, Borya can visit all doctors on days 10 and 11.

 

这个题我没有看到是按顺序的,GG

按顺序之后就找到每个点的最小值就好了,就是一个不等式

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int main()
{
    ll n,m=0;
    cin>>n;
    for(int i=0; i<n; i++)
    {
        int a,b;
        cin>>a>>b;
        if(m<a)m=a;
        else
        {
            ll k=(m-a)/b+1;
            m=a+k*b;
        }
    }
    cout<<m<<endl;
    return 0;
}
B. Table Tennis
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

n people are standing in a line to play table tennis. At first, the first two players in the line play a game. Then the loser goes to the end of the line, and the winner plays with the next person from the line, and so on. They play until someone wins k games in a row. This player becomes the winner.

For each of the participants, you know the power to play table tennis, and for all players these values are different. In a game the player with greater power always wins. Determine who will be the winner.

Input

The first line contains two integers: n and k (2 ≤ n ≤ 500, 2 ≤ k ≤ 1012) — the number of people and the number of wins after which a player leaves, respectively.

The second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ n) — powers of the player. It's guaranteed that this line contains a valid permutation, i.e. all ai are distinct.

Output

Output a single integer — power of the winner.

Examples
input
2 2
1 2
output
2 
input
4 2
3 1 2 4
output
3 
input
6 2
6 5 3 1 2 4
output
6 
input
2 10000000000
2 1
output
2
Note

Games in the second sample:

3 plays with 1. 3 wins. 1 goes to the end of the line.

3 plays with 2. 3 wins. He wins twice in a row. He becomes the winner.

给你n个人,如果这个人输了就到队列尾部,然后模拟下 

这个B本来队列模拟就错了,结果雪上加霜,因为我输了就意味着下一个人赢了啊,欢快的打出GG

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll a[1005];
int main()
{
    ll n,k;
    cin>>n>>k;
    for(int i=0; i<n; i++)
        cin>>a[i];
    ll mm=a[0],t=0;
    for(int i=1; i<n; i++)
    {
        if(t>=k)
        {
            cout<<mm;
            return 0;
        }
        if(mm>a[i])
            t++;
        else
            mm=a[i],t=1;
    }
    cout<<mm<<endl;
    return 0;
}
C. Short Program
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

Petya learned a new programming language CALPAS. A program in this language always takes one non-negative integer and returns one non-negative integer as well.

In the language, there are only three commands: apply a bitwise operation AND, OR or XOR with a given constant to the current integer. A program can contain an arbitrary sequence of these operations with arbitrary constants from 0 to 1023. When the program is run, all operations are applied (in the given order) to the argument and in the end the result integer is returned.

Petya wrote a program in this language, but it turned out to be too long. Write a program in CALPAS that does the same thing as the Petya's program, and consists of no more than 5 lines. Your program should return the same integer as Petya's program for all arguments from 0 to 1023.

Input

The first line contains an integer n (1 ≤ n ≤ 5·105) — the number of lines.

Next n lines contain commands. A command consists of a character that represents the operation ("&", "|" or "^" for AND, OR or XOR respectively), and the constant xi 0 ≤ xi ≤ 1023.

Output

Output an integer k (0 ≤ k ≤ 5) — the length of your program.

Next k lines must contain commands in the same format as in the input.

Examples
input
3
| 3
^ 2
| 1
output
2
| 3
^ 2
input
3
& 1
& 3
& 5
output
1
& 1
input
3
^ 1
^ 2
^ 3
output
0
Note

You can read about bitwise operations in https://en.wikipedia.org/wiki/Bitwise_operation.

Second sample:

Let x be an input of the Petya's program. It's output is ((x&1)&3)&5 = x&(1&3&5) = x&1. So these two programs always give the same outputs.

 

 给你位运算,让你写操作

对于每一位
^1 取反
&0 清空
|1 赋值

那就搞这三个操作好了

#include <cstdio>
const int N=5e5+5;
char a[N];
int b[N],F[10][2],fh[10][4];
int main()
{
    int n;
    scanf("%d",&n);
    for(int i=1; i<=n; i++)
    {
        getchar();
        scanf("%c %d",&a[i],&b[i]);
    }
    int x=1;
    for(int i=0; i<10; i++)
    {
        int y=x,z=0;
        for(int j=1; j<=n; j++)
        {
            if(a[j]=='|')
                z|=b[j],y|=b[j];
            else if(a[j]=='&')
                z&=b[j],y&=b[j];
            else
                z^=b[j],y^=b[j];
        }
        y>>=i,z>>=i;
        F[i][1]=y&1,F[i][0]=z&1;
        x<<=1;
    }
    int f1=0,f2=0,f3=0;
    for(int i=0; i<10; i++)
    {
        if(F[i][1]&&!F[i][0])
            fh[i][0]=1;
        else if(F[i][1]&&F[i][0])
            fh[i][0]=1,fh[i][1]=1;
        else if(!F[i][1]&&!F[i][0])
            fh[i][0]=0;
        else
            fh[i][0]=1,fh[i][2]=1;
    }
    for(int i=9; i>=0; i--)
    {
        f1=f1*2+fh[i][0];
        f2=f2*2+fh[i][1];
        f3=f3*2+fh[i][2];
    }
    printf("3\n& %d\n| %d\n^ %d\n",f1,f2,f3);
    return 0;
}

 

posted @ 2017-10-27 07:55  暴力都不会的蒟蒻  阅读(765)  评论(0编辑  收藏  举报