using namespace std;
int fun(int n)
{
int sum=1;
int i;
for(i=1;i<=n;i++)
sum*=i;
return sum;
}
int main()
{
int i,mark=1;
int sum=0,item=0;
for(i=1;i<=9;i++)
{
item=mark*fun(i);
sum+=item;
mark=-mark;
}
cout<<"1!-2!+3!-4!+5!-6!+7!-8!+9!="<<sum<<endl;
}
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