delete pics to save space

1.1009.cpp

@@ -0,0 +1,124 @@
+// luogu-judger-enable-o2
+#include<vector>
+#include<cstdio>
+#include<queue>
+#include<string>
+#include<cstring>
+#include<algorithm>
+#include<cmath>
+int CacheSize=10;//try to use the cache
+struct BigInt
+{
+	bool f;
+	std::vector<int> num;
+	static const int base=100000000;
+	BigInt()
+	{
+		f=0;
+		num.push_back(0);
+	}
+	void format()
+	{
+		while(num.size()>1&&num[num.size()-1]==0) num.erase(num.end()-1);
+		if(num.size()==1&&num[0]==0) f=0;
+	}
+	//Input and Output
+	char* c_str()
+	{
+		char *p;
+		p=new char[num.size()*8+16];
+		memset(p,0,sizeof(p));
+		if(f) sprintf(p,"-");
+		sprintf(p,"%s%d",p,num[num.size()-1]);
+		for(int i=num.size()-2;i>=0;i--) sprintf(p,"%s%08d",p,num[i]);
+		return p;
+	}
+	BigInt operator=(int v)
+	{
+		f=0;
+		if(v<0)
+		{
+			f=1;
+			v=-v;
+		}
+		std::queue<int> q;
+		if(v==0) q.push(0);
+		else
+			while(v>0)
+			{
+				q.push(v%base);
+				v/=base;
+			}
+		num.resize(q.size());
+		for(int i=0;q.size()>0;i++)
+		{
+			num[i]=q.front();
+			q.pop();
+		}
+		return *this;
+	}
+	BigInt operator+(BigInt& b)
+	{
+		format();
+		b.format();
+		BigInt c;
+		int t=0,t2=std::max(num.size(),b.num.size())+1;
+		c.num.resize(t2);
+		memset(&c.num[0],0,t2*4);
+		for(int i=0;i<t2;i++)
+		{
+			if(i<num.size()) t+=num[i];
+			if(i<b.num.size()) t+=b.num[i];
+			c.num[i]=t%base;
+			t/=base;
+		}
+		c.format();
+		return c;
+	}
+	BigInt operator*(BigInt& b)
+	{
+		format();
+		b.format();
+		BigInt c;
+		c.num.resize(num.size()+b.num.size());
+		memset(&c.num[0],0,(num.size()+b.num.size())*4);
+		int i,j,k,I,J;
+		long long t;
+		for(i=0;i*CacheSize<num.size();i++)
+			for(j=0;j*CacheSize<b.num.size();j++)
+				for(I=i*CacheSize;I<(i+1)*CacheSize&&I<num.size();I++)
+					for(J=j*CacheSize;J<(j+1)*CacheSize&&J<b.num.size();J++)
+					{
+						t=(long long)num[I]*b.num[J];
+						t+=c.num[I+J];
+						c.num[I+J]=t%base;
+						k=I+J+1;
+						t/=base;
+						while(t>0)
+						{
+							t+=c.num[k];
+							c.num[k++]=t%base;
+							t/=base;
+						}
+					}
+		c.f=(f!=b.f);
+		c.format();
+		return c;
+	}
+};
+using namespace std;
+int main()
+{
+	BigInt res,t,t2;
+	t=1;
+	int n;
+	scanf("%d",&n);
+	for(int i=1;i<=n;i++)
+	{
+		t2=i;
+		t=t*t2;
+		res=res+t;
+	}
+	printf("%s\n",res.c_str());
+	return 0;
+}