[bzoj1101]Zap

 1 #include
 2 using namespace std;
 3 #define N 50001
 4 int t,n,m,k,ans,mu[N],vis[N],p[N];
 5 void mobius(){
 6     mu[1]=1;
 7     for(int i=2;i){
 8         if (!vis[i]){
 9             p[++p[0]]=i;
10             mu[i]=-1;
11         }
12         for(int j=1;i*p[j]){
13             vis[i*p[j]]=1;
14             if (i%p[j])mu[i*p[j]]=-mu[i];
15             else{
16                 mu[i*p[j]]=0;
17                 break;
18             }
19         }
20     }
21     for(int i=1;i1]; 
22 }
23 int main(){
24     scanf("%d",&t);
25     mobius();
26     while (t--){
27         scanf("%d%d%d",&n,&m,&k);
28         n/=k;
29         m/=k;
30         ans=0;
31         for(int i=1,j;i<=min(n,m);i=j+1){
32             j=min(n/(n/i),m/(m/i));
33             ans+=(mu[j]-mu[i-1])*(n/i)*(m/i); 
34         }
35         printf("%d\n",ans);
36     }
37 }

View Code

 

转载于:https://www.cnblogs.com/PYWBKTDA/p/11247985.html