网友222.70.181.*     #include<iostream> using namespace std; bool IsUglyNum( int nNum, int* pNum, int nCur ); int CalUglyNum( int nIndex ) {  if( nIndex > 4 )  {  int *pNum;  int nCur = 3;    pNum = new int[ nIndex ];  int nNum = 6;  pNum[ 0 ] = 2;  pNum[ 1 ] = 3;  pNum[ 2 ] = 4;  pNum[ 3 ] = 5;  bool bContinue = true;  for( int nCount = 4; nCount < nIndex; )  {  while( bContinue )  {  if( IsUglyNum( nNum, pNum, nCur ) )  {  pNum[ ++nCur ] = nNum;  nCount++;  nNum++;  bContinue = false;  }  else  nNum++;  }  bContinue = true;  } delete []pNum; return --nNum;  }  else  {  switch( nIndex )  {  case 1:  return 2;  case 2:  return 3;  case 3:  return 4;  case 4:  return 5;  default:  return 0;  }  } } bool IsUglyNum( int nNum, int* pNum, int nCur ) {  if( nCur < 0 )  return false;  if( !( nNum % pNum[ nCur ] ) )  {  nNum /= pNum[ nCur ];  if( nNum == 1 )  return true;  else  return IsUglyNum( nNum, pNum, nCur );  }  else  {  return IsUglyNum( nNum, pNum, nCur - 1 );  } } int main() {  int nIndex;  cout << "please input a number between 1 to 200: ";  cin >> nIndex;  if( nIndex < 1 || nIndex > 200 )  cout << "out of range!" << endl;  else  cout << "the ugly number is: " << CalUglyNum( nIndex-1);  return 1; }   网友 dead_fox#include<iostream.h> #include<stdlib.h> bool fon(int n); int main() { int m,j=0,k=0; cout<<"请输入1~200间的一个正整数"<<endl; cin>>m; if(m<1||m>200) { cout<<"输入错误!"<<endl; exit(0); } while(k<m) { j++; if(fon(j)) k++; } cout<<"第 "<<m<<" 个Ugly数是: "<<j<<endl<<endl; system("pause"); return 0; } bool fon(int n) { if(n==1) return 1; while(!(n%2)) { n/=2; if(n==1) return 1; } while(!(n%3)) { n/=3; if(n==1) return 1; } while(!(n%5)) { n/=5; if(n==1) return 1; } return 0; } //不知道为什么我不能登陆——dead_fox 网友  222.173.180.*     int main() {  long num=0,i=0,j=0,k=0; printf("please input number(<=200):\n"); scanf("%d",&num); while(i++,j!=num) { k=i; while(k%2?false:k>>=1); while(k%3?false:k/=3); while(k%5?false:k/=5); if(k==1) j++; } printf("\n%d\n",--i); return 0; }

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