gordon321 @ 2023-08-03 14:41:51
#include<bits/stdc++.h>
using namespace std;
int jc(int a){
int ns=1;
for(int i=1;i<=a;i++){
ns=ns*i;
}
return ns;
}
int main(){
long long a;
long long ans=0;
cin>>a;
for(int i=1;i<=a;i++){
ans=ans+jc(i);
}
cout<<ans;
return 0;
} by SealMoBurp @ 2023-08-03 14:42:40
使用Python
by Rieman_sum @ 2023-08-03 14:43:34
@gordon321 bdfs高精度教程
by EricWan @ 2023-08-03 14:43:42
你这是《高精度》？
by EricWan @ 2023-08-03 14:44:49
long long 肯定存不下，只少得自己写个int256
by gordon321 @ 2023-08-03 14:45:59
能不能帮忙改一下完整程序
by Zona @ 2023-08-03 14:51:54
@gordon321 建议先做P1303和P1601把高精度学了，以及右转题解区
by zlg2011111 @ 2023-08-06 16:31:18
“求助！！！只拿到50分”讨论版有代码答案
by _ant_ant @ 2023-08-09 12:24:56
@Seal_ZhouMoTong
妖妖灵，这里出了一个叛徒！
by _ant_ant @ 2023-08-09 12:26:13
《long long度》
by _ant_ant @ 2023-08-09 12:27:05
#include<bits/stdc++.h>
using namespace std;
struct Bigint{
int len,a[101]={0};
Bigint(int x=0){
for(len=1;x;len++)
a[len]=x%10,x/=10;
len--;
}
int &operator[](int i){
return a[i];
}
void flatten(int L){
len=L;
for(int i=1;i<=len;i++)
a[i+1]+=a[i]/10,a[i]%=10;
for(;!a[len];)
len--;
}
void print(){
for(int i=max(len,1);i;i--)
printf("%d",a[i]);
}
};
Bigint operator+(Bigint a,Bigint b){
Bigint c;
int len=max(a.len,b.len);
for(int i=1;i<=len;i++)
c[i]+=a[i]+b[i];
c.flatten(len+1);
return c;
}
Bigint operator*(Bigint a,int b){
Bigint c;
int len=a.len;
for(int i=1;i<=len;i++)
c[i]=a[i]*b;
c.flatten(len+11);
return c;
}
int n;
Bigint ans(0),fac(1);
int main(){
scanf("%d",&n);
for(int i=1;i<=n;i++){
fac=fac*i;
ans=ans+fac;
}
ans.print();
return 0;
}