ivan11 @ 2024-05-01 11:20:06
include<iostream>
#include<cstring>
#include<string>
using namespace std;
const int len = 5005;
struct big
{
long long l;
long long a[len];
void clear()
{
for(int i=l;i>=2;--i)
{
if(!a[i]) -- l;
else break ;
}
return ;
}
void in()
{
string s;
cin>>s;
l=s.length();
for(int i=1;i<=l;++i)
{
a[i] = (s[l-i] & 15);
}
return ;
}
void out()
{
clear();
for(int i=l;i>=1;--i)
{
cout<<a[i];
}
cout<<'\n';
return ;
}
big operator + (big b)const
{
big c;
memset(c.a,0,sizeof(c.a));
c.l = max(l,b.l) + 1;
for(int i=1;i<=c.l;++i)
{
c.a[i] += a[i] + b.a[i];
c.a[i+1] = c.a[i] / 10;
c.a[i] %= 10;
}
return c;
}
big operator * (int b)const
{
big c;
memset(c.a,0,sizeof(c.a));
c.l = l + 1;
for(int i=1;i<=l;++i)
{
c.a[i] += a[i] * b;
}
for(int i=1;i<=c.l;++i)
{
c.a[i+1] += c.a[i] / 10;
c.a[i] %= 10;
}
return c;
}
}num,ans;
long long n;
int main()
{
cin>>n;
memset(num.a,0,sizeof(num.a));
memset(ans.a,0,sizeof(ans.a));
num.l=1;
num.a[1]=1;
ans.l=1;
ans.a[1]=1;
for(int i=2;i<=n;++i)
{
num = num * i;
ans = ans + num;
}
ans.out();
return 0;
}by MuYuMC @ 2024-06-07 20:56:29
你这有些复杂啊
#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <cstdio>
#include <iomanip>
using namespace std;
int A[2000];
int B[2000];
int sum[99999];
void cheng()
{
int i;
for(i = 1;i <= A[0];i++)
{
A[i] = A[i] * B[i];
}
for(i = 1;i <= A[0];i++)
{
A[i + 1] += A[i] / 10;
A[i] = A[i] % 10;
}
while(A[i] != 0)
{
A[i + 1] += A[i] / 10;
A[i] = A[i] % 10;
A[0]++;
i++;
}
}
int main()
{
int n,i,k;
string s1,s2;
cin >> s1 >> s2;
A[0] = s1.size();
B[0] = s2.size();
for(i = 1;i <= s1.size();i++)
{
A[i] = s1[A[0] - i] - '0';
}
for(i = 1;i <= s2.size();i++)
{
B[i] = s2[B[0] - i] - '0';
}
cheng();
for(i = A[0];i >= 1;i--)
{
cout << A[i];
}
return 0;
}