#include <iostream.h>
void aaa(double p,double q,double m,double mp,int n)
{
  int t=(int)(m/q)+1;
  if(p*t<mp){cout<<n+t;}
  else { aaa(p,q,1-q*t+m,1-p*t+mp,n+t);}
}
void main()
{
  double 1p,q;
  cin>>p>>q;
  p/=100;
  q/=100;
  aaa(p,q,1,1,0);
}

Your program is wrong, though you got AC!
When P=22.39, Q=22.5, your answer is 40, according to your program. But the correct answer is 49. Because 40*22.39%=8.956, and 40*22.5%=9. There is no such integer n, 8.956<n<9.
49*22.39%=10.9711,49*22.5%=11.025.See,10.9711<11<11.025
My program has only 15 lines, too.

#include<iostream.h>
#include<math.h>
void main(){
    double P,Q;
    cin>>P>>Q;
    int number=1,min=1,max=0;
    while(min>=max)
    {
        min=(int)(number*P*100)/10000+1;
        max=(int)(number*Q*100)/10000;
        if((int)(number*Q*100)%10000!=0)max++;
        number++;
    }
    cout<<(number-1)<<endl;
}

Edited by author 21.04.2004 00:58

#include <iostream.h>

int main()
{
    double p,q;
    int x=1;
    cin>>p>>q;
    while(((int)(x*q/100)-(int)(x*p/100))!=1)
    {
        x++;
        if(((x*q/100)-(int)(x*q/100))==0||((x*p/100)-(int)(x*p/100))==0)
        x++;
    }
    cout<<x<<endl;
    return 0;
}

Hey man,
Check your program.
Try to take p = 0,01;q=0,20 your program will give 500!
500*0,01/100=0,05
500*0,2/100=1

So, the right answer is 501!

14 lines
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
double p,q;
cin>>p>>q;
p/=100.;
q/=100.;
long long n=1;
while(ceil(n*q)-ceil(n*p) < 1) n++;
cout<<n;
return 0;
}

As said your program is wrong... and LAAAARGE)... and is void...

#include <stdio.h>
int main()
{
    float ans=0, P, Q;
    scanf("%f%f",&P,&Q);
    for(;;){
        float f1=ans*P/100.0f,f2=(ans++)*Q/100.0f,i=int(f2);
        if(i)if((i>f1)&&(i<f2)){printf("%.0f\n",--ans);return 0;}
    }
}

there is something wrong in test 5...

#include <stdio.h>
#include <math.h>
int main(){double p,q;scanf("%lf%lf",&p,&q);int x=1,m=floor(p*100.0+0.5),n=floor(q*100.0+0.5);while( (m*x/10000+1) >= (n*x/10000+(n*x%10000?1:0)) )++x;printf("%d\n",x);return 0;}

Just make a joke!