huge factorial
What is wrong with my program? The answer is little off.
This is for calculating factorial
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
|
#include<iostream>
using namespace std;
int main()
{
int t;
cin>>t;
while(t>0)
{
int n;
cin>>n;
int str[200];
str[0]=1;
for(int i=1;i<200;i++)
str[i]=0;
int i=0;
int carry=0,pos=0;
while(n>0)
{
pos=0;
carry=0;
while(pos<=i)
{
int x=(str[pos]*n)+carry;
carry=x/10;
str[pos]=x%10;
pos++;
}
while(carry>0)
{
str[pos]=carry%10;
carry/=10;
i++;
pos++;
}
n--;
}
for(int j=i;j>=0;j--)
cout<<str[i];
cout<<endl;
t--;
}
}
| |
Why not use a recursive function? It may be slower for bigger numbers but its less code
1 2 3 4 5 6 7
|
int factorial(int n)
{
if(n > 1)
return n * factorial(n - 1);
else
return 1;
}
| |
Take a look at line 38.
After fixing that. Try making your program even better by allowing arbitrarily large inputs instead of only allowing integers up to 200 digits.
@kingkush
but 100! won't fit in int
Topic archived. No new replies allowed.