Codeforces Round #412

第一题水题，8分钟1a

#include<map>
#include<set>
#include<cmath>
#include<queue>
#include<stack>
#include<vector>
#include<cstdio>
#include<cassert>
#include<iomanip>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
#define pi acos(-1)
#define ll long long
#define mod 1000000007
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#pragma comment(linker, "/STACK:1024000000,1024000000")

using namespace std;

const double g=10.0,eps=1e-;
const int N=+,maxn=+,inf=0x3f3f3f3f;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie();
    int n;
    cin>>n;
    int last;
    bool maybe=,rate=;
    for(int i=;i<n;i++)
    {
        int a,b;
        cin>>a>>b;
        if(i==)last=a;
        else
        {
            if(last<a)maybe=;
            last=a;
        }
        if(a!=b)rate=;
    }
    if(rate)cout<<"rated"<<endl;
    else if(!rate&&maybe)cout<<"unrated"<<endl;
    else if(!rate&&!maybe)cout<<"maybe"<<endl;
    return ;
}

A

第二题暴力模拟一下，每次加（减）50，先减再加

#include<map>
#include<set>
#include<cmath>
#include<queue>
#include<stack>
#include<vector>
#include<cstdio>
#include<cassert>
#include<iomanip>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
#define pi acos(-1)
#define ll long long
#define mod 1000000007
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#pragma comment(linker, "/STACK:1024000000,1024000000")

using namespace std;

const double g=10.0,eps=1e-;
const int N=+,maxn=+,inf=0x3f3f3f3f;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie();
    int p,x,y,ans=;
    cin>>p>>x>>y;
    for(int i=x;i>=y;i-=)
    {
        int j=(i/)%;
        for(int k=;k<=;k++)
        {
            j=(j*+)%;
            if(j+==p)
            {
                ans=i;
                break;
            }
        }
        if(ans)break;
    }
    if(ans)
    {
        cout<<<<endl;
        return ;
    }
    for(int i=x;;i+=)
    {
        int j=(i/)%;
        for(int k=;k<=;k++)
        {
            j=(j*+)%;
            if(j+==p)
            {
                ans=i;
                break;
            }
        }
        if(ans)break;
    }
    int res=(ans-x+)/;
    cout<<res<<endl;
    return ;
}

B

第三题wa了6发，终于O（1）过了，数据1e9早该想到算法有问题

#include<map>
#include<set>
#include<cmath>
#include<queue>
#include<stack>
#include<vector>
#include<cstdio>
#include<cassert>
#include<iomanip>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
#define pi acos(-1)
#define ll long long
#define mod 1000000007
#define ls l,m,rt<<1
#define rs m+1,r,rt<<1|1
#pragma comment(linker, "/STACK:1024000000,1024000000")

using namespace std;

const double g=10.0,eps=1e-;
const int N=+,maxn=+,inf=0x3f3f3f3f;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie();
    ll x,y,p,q;
    int t;
    cin>>t;
    while(t--){
        cin>>x>>y>>p>>q;
        if(p==q)
        {
            if(x==y)cout<<<<endl;
            else cout<<-<<endl;
            continue;
        }
        if(p==)
        {
            if(x==)cout<<<<endl;
            else cout<<-<<endl;
            continue;
        }
        ll k1=(y-x)/(q-p);
        if((y-x)%(q-p)!=)k1++;
        ll k2=x/p;
        if(x%p!=)k2++;
        ll k3=y/q;
        if(y%q!=)k3++;
        ll k=max(k1,max(k2,k3));
        cout<<k*q-y<<endl;
    }
    return ;
}

C