sidereal

注意corridor只有200个，第n个corridor对应room 2n-1和2n 1 #include <stdio.h> 2 #include <string.h> 3 #include <algorithm> 4 5 using namespace std; 6 int corridor[201]; 7 bool compare(int a,int b) 8 { 9 return a>b;10 }11 int main()12 {13 int cases;14 int n;15 int from,to;16 int start,end;17 . Read More

求出素数表之后暴力搜索 1 #include <stdio.h> 2 #include <string.h> 3 int prime[10000]; 4 bool number[10001]; 5 int constructPrime(int n) 6 { 7 int i,j; 8 int pc=0; 9 memset(number,false,sizeof(number));10 for(i=2;i<=n;i++)11 if(!number[i])12 {13 prime[pc++]=i;14 ... Read More

如果n是素数，则2n,3n,4n....都是合数1 void GenPrimes (int n){2 int i , j , k; pc = 0;3 memset (mk , false , n +1);4 for(i=2; i <=n; i++)5 if (! mk[i]){6 primes [pc ++] = i;7 for(j=i+i; j <=n; j+=i) mk[j] = true ;8 }9 } Read More