Poj2247 Humble Numbers

来源：互联网发布：数据库求质数的代码编辑：程序博客网时间：2024/06/05 17:29

//提高前面计算的利用率，避免重复计算

#include<iostream>
#include<cstdio>
using namespace std;
int rank[5843],r=2,a2=1,a3=1,a5=1,a7=1;
void cal(int x){
while(r<=x){
  int count[5]={0,0,0,0,0};
  if(rank[a2]*2<=rank[a3]*3&&rank[a2]*2<=rank[a5]*5&&rank[a2]*2<=rank[a7]*7){
   rank[r]=rank[a2]*2;
   count[0]++;
   count[4]++;
  }
  if(rank[a3]*3<=rank[a2]*2&&rank[a3]*3<=rank[a5]*5&&rank[a3]*3<=rank[a7]*7){
   rank[r]=rank[a3]*3;
   count[1]++;
   count[4]++;
  }
  if(rank[a5]*5<=rank[a2]*2&&rank[a5]*5<=rank[a3]*3&&rank[a5]*5<=rank[a7]*7){
   rank[r]=rank[a5]*5;
   count[2]++;
   count[4]++;
  }
  if(rank[a7]*7<=rank[a2]*2&&rank[a7]*7<=rank[a5]*5&&rank[a7]*7<=rank[a3]*3){
   rank[r]=rank[a7]*7;
   count[3]++;
   count[4]++;
  }
  if(count[4]!=0)r++;
  if(count[0]!=0)a2++;
  if(count[1]!=0)a3++;
  if(count[2]!=0)a5++;
  if(count[3]!=0)a7++;
}
}
int main(void){
int i;
rank[1]=1;
while(1){
  scanf("%d",&i);
  if(i==0)break;
  else if(i>=r)cal(i);
  if(i%100!=11&&i%10==1)printf("The %dst humble number is %d.\n",i,rank[i]);
  else if(i%100!=12&&i%10==2)printf("The %dnd humble number is %d.\n",i,rank[i]);
  else if(i%100!=13&&i%10==3)printf("The %drd humble number is %d.\n",i,rank[i]);
  else printf("The %dth humble number is %d.\n",i,rank[i]);
}
return 0;
}

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