CF练习——2020暑假第二周

题目链接：
https://codeforces.com/gym/287615
https://codeforces.com/gym/287849

A. Omkar and Completion

签到、找规律

/*
* problem:Omkar and Completion
* method:签到
* date:2020/07/15
*/
#include<iostream>
#define ll long long
using namespace std;
const int maxn=1005;
int a[maxn],n,t;
int main(){
	cin>>t;
	while(t--){
        int i;
		cin>>n;
		for(i=0;i<n;i++){
			cout<<1;
			if(i!=n-1) cout<<' ';
		}
		cout<<endl;
	}
	return 0;
}

B. Omkar and Last Class of Math

找规律、LCM

/*
* problem:Omkar and Last Class of MAth
* method:规律
* date:2020/07/15
*/
#include<iostream>
#define ll long long
using namespace std;
const ll maxn=1005;
int n,t;
int main(){
	int i,j;
	cin>>t;
	while(t--){
		cin>>n;
		int a,b;
		for(i=2;i*i<=n;i++){
			if(n%i==0){
				int a=n/i;
				cout<<a<<' '<<n-a<<endl;
				break;
			}
		}
		if(i*i>n) cout<<1<<' '<<n-1<<endl;
	}
	return 0;
}

C. Omkar and Baseball

找规律：需要的exchange次数为{0,1,2}

/*
* problem:Omkar and Baseball
* method:找规律
* date:2020/07/19
*/
#include<iostream>
#define ll long long
using namespace std;
ll t,n,x[200005];
int main(){
	ll i,j,cnt;
	cin>>t;
	while(t--){
		int flag=0;
		cin>>n;
		cnt=0;
		for(i=1;i<=n;i++){
			cin>>x[i];
			if(x[i]==i) cnt++;
		}
		if(cnt==n) cout<<"0"<<endl;
		else{
			for(i=1;x[i]==i;i++) cnt--;
			for(i=n;x[i]==i;i--) cnt--;
			if(cnt==0) cout<<"1"<<endl;
			else cout<<"2"<<endl;
		}
	}
	return 0;
}

A. Magical Sticks

找规律：递增数列规律

/*
* problem:Magical Sticks
* method:找规律（数列和规律）
* date:2020/07/19
*/
#include<iostream>
#include<cmath>
#define ll long long
using namespace std;
ll t,n;
int main(){
	cin>>t;
	while(t--){
		cin.tie(0);
		cout.tie(0);
		cin>>n;
		ll t=n/2;
		if(2*t!=n) cout<<t+1<<endl;
		else cout<<t<<endl;
	}
	return 0;
}

B. Magical Calendar

找规律：数列

/*
* problem:Magical Calendar
* method:找规律（数列）
* date:2020/07/19
*/
#include<iostream>
#define ll long long
using namespace std;
ll t,x,y;
int main() {
	cin>>t;
	while(t--) {
		cin>>x>>y;
		if(x>y) {
			cout<<(y+1)*y/2<<endl;
		} else {
			cout<<(x-1)*x/2+1<<endl;
		}
	}
	return 0;
}

C. A Cookie for You

找规律：大小

/*
* problem: A Cookie for You
* method:找规律（大、小）
* date:2020/07/19
*/
#include<iostream>
#define ll long long
using namespace std;
ll t,a,b,n,m;
int main() {
	cin>>t;
	while(t--) {
		cin>>a>>b>>n>>m;
		if(a+b>=m+n) {
			if(a<b) {
				a^=b;
				b^=a;
				a^=b;
			}
			if(b<m) cout<<"No"<<endl;
			else cout<<"Yes"<<endl;
		} else {
			cout<<"No"<<endl;
		}

	}
	return 0;
}

D. Grid-00100

找规律：矩阵

/*
* problem:Grid-00100
* method:找规律
* date:2020/07/19
*/
#include<iostream>
#define ll long long
using namespace std;
int t,n,k;
int x[305][305];
int main(){
	int i,j;
	cin>>t;
	while(t--){
		cin>>n>>k;
		for(i=0;i<n;i++){
			for(j=0;j<n;j++)
				x[i][j]=0;
		}
		if(k%n) cout<<"2"<<endl;
		else cout<<"0"<<endl;
		i=0;j=0;
		while(k--){
			if(i==0){
				while(x[i][j]) j++;
			}
			x[i][j]=1;
			i=(i+1)%n;
			j=(j+1)%n;
		}
		for(i=0;i<n;i++){
			for(j=0;j<n;j++)
				cout<<x[i][j];
			cout<<endl;
		}
	}
	return 0;
}