[BZOJ 2301] [HAOI2011] Problem b

 1 #include <cstdio>
 2 #define min(x,y) x<y?x:y
 3 using namespace std;
 4 int mu[50010];
 5 bool chk[50010];
 6 int prime[50010],tot=0;
 7 long long getsum(int x,int y) {
 8     long long re=0;
 9     int f=min(x,y),la;
10     for (int i=1;i<=f;i=la+1) {
11         la=min(x/(x/i),y/(y/i));
12         re+=(long long)(x/i)*(y/i)*(mu[la]-mu[i-1]);
13     }
14     return re;
15 }
16 int main() {
17     //scanf("%d",&n);
18     mu[1]=1;
19     for (int i=2;i<=50000;++i) {
20         if (!chk[i]) {
21             prime[++tot]=i;
22             mu[i]=-1;
23         }
24         for  (int j=1;j<=tot&&i*prime[j]<=50000;++j) {
25             chk[i*prime[j]]=1;
26             if(i%prime[j]==0) {
27                 mu[i*prime[j]]=0;
28                 break;    
29             }
30             mu[i*prime[j]]=-mu[i];
31         }
32     }
33     mu[0]=0;
34     for (int i=2;i<=50000;++i) mu[i]+=mu[i-1];
35     int t;
36     scanf("%d",&t);
37     while(t--) {
38         int a,b,c,d,k;
39         scanf("%d%d%d%d%d",&a,&b,&c,&d,&k);
40         printf("%lld\n",getsum(b/k,d/k)-getsum((a-1)/k,d/k)-getsum(b/k,(c-1)/k)+getsum((a-1)/k,(c-1)/k));
41     }    
42     return 0;
43 }