d(x)表示x的约数个数，让你求（l,r<=10^12,r-l<=10^6,k<=10^7）

 

#include
     
      using namespace std;#define MOD 998244353ll#define MAXP 1000100typedef long long ll;ll x,y;int T,K;bool isNotPrime[MAXP+10];int num_prime,prime[MAXP+10];void shai(){    for(long i = 2 ; i <  MAXP ; i ++)      {          if(! isNotPrime[i])              prime[num_prime ++]=i;          for(long j = 0 ; j < num_prime && i * prime[j] <  MAXP ; j ++)          {              isNotPrime[i * prime[j]] = 1;              if( !(i % prime[j]))                  break;          }      }  }ll b[1000010],a[1000010];int main(){	scanf("%d",&T);	shai();	for(;T;--T){		scanf("%lld%lld%d",&x,&y,&K);		for(ll i=x;i<=y;++i){			a[i-x+1ll]=i;			b[i-x+1ll]=1;		}		for(int i=0;i
      
       1ll)){				b[i-x+1ll]=(b[i-x+1ll]*((ll)K+1ll))%MOD;			}			ans=(ans+b[i-x+1ll])%MOD;		}		printf("%lld\n",ans);	}	return 0;}