The GNU Compiler Collection (usually shortened to GCC) is a compiler system produced by the GNU Project supporting various programming languages. But it doesn’t contains the math operator “!”.
In mathematics the symbol represents the factorial operation. The expression n! means "the product of the integers from 1 to n". For example, 4! (read four factorial) is 4 × 3 × 2 × 1 = 24. (0! is defined as 1, which is a neutral element in multiplication,
not multiplied by anything.)
We want you to help us with this formation: (0! + 1! + 2! + 3! + 4! + ... + n!)%m
The first line consists of an integer T, indicating the number of test cases.
Each test on a single consists of two integer n and m.
Output the answer of (0! + 1! + 2! + 3! + 4! + ... + n!)%m.
Constrains
0 < T <= 20
0 <= n < 10^100 (without leading zero)
0 < m < 1000000
593846
求 n!%m=(n-1)!*n%m; 即f(n)=f(n-1)*n%m;
而且 (0!+1!+...n!)%m 如果n>m 那么以后的k!都可以被m整除。。忽略
然后 。。递推就可以了
#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <cctype>
#include <cmath>
#include <cstdlib>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <list>
#define ll long long
using namespace std;
const int INF=1<<27;
const int maxn=1010;
int main()
{
int t;
char n[200];int m;
scanf("%d",&t);
while(t--)
{
scanf("%s %d",n,&m);
int tem;
if(strlen(n)>=7)
tem=999999;
else
sscanf(n,"%d",&tem);
tem=min(m,tem);
ll f1=1%m,fn,ans=f1;
for(int i=1;i<=tem;i++)
{
fn=f1*i%m;
ans+=fn;
f1=fn;
}
printf("%lld\n",ans%m);
}
return 0;
}