```cpp
//P1319 压缩技术
#include<bits/stdc++.h>
#include<cstring>
#include<stack>
#include<queue>
#include<vector>
#define ll long long
#define ld long double
#define ull unsigned long long
using namespace std;
int N;
int a[40086];
int main(){
	cin>>N;
	int sum=0;
	int len=0;
	for(int i=1;;i++){
		cin>>a[i];
		sum+=a[i];
		len++;
		if(sum==N*N) break;
	}
	int cnt=0;
	for(int i=1;i<=len;i++){
		for(int j=1;j<=a[i];j++){
			if(i%2==0) cout<<1;
			else cout<<0;
			cnt++;
			if(cnt==N){
				cout<<"\n"; cnt=0;
			}
		}
	}
	return 0;
}
```

```cpp
//B3620 x 进制转 10 进制
#include<bits/stdc++.h>
#include<cstring>
#include<stack>
#include<queue>
#include<vector>
#define ll long long
#define ld long double
#define ull unsigned long long
using namespace std;
int to_dec(string n,int x){//n转10 
	int res=0; int cnt=1;
	for(int i=n.length()-1;i>=0;i--){
		if(n[i]>='A'&&n[i]<='Z') res+=(n[i]-'A'+10)*pow(x,cnt-1);
		else res+=(n[i]-'0')*pow(x,cnt-1);
		cnt++;
	}
	return res;
}
int main(){
	int x; string n;
	cin>>x>>n;
	cout<<to_dec(n,x);
	return 0;
}
```

```cpp
//P1424 小鱼的航程（改进版）
#include<bits/stdc++.h>
#include<cstring>
#include<stack>
#include<queue>
#include<vector>
#define ll long long
#define ld long double
#define ull unsigned long long
using namespace std;
int x,n;
int main(){
	ll ans=0;
	cin>>x>>n;
	for(int i=1;i<=n;i++){
		if(x>=1&&x<=5) ans+=250;
		x++;
		if(x==8) x=1;
	}
	cout<<ans;
	return 0;
}

**
```