#include<iostream>
using namespace std;

int main(){
    int petr,a,taxi,b;
    int temp;

    while(cin>>petr>>a>>taxi>>b){
        if(petr>=taxi)cout<<petr<<endl;

        else{
            temp=taxi-petr;
            if(a<=b){
                while(temp>b){
                    petr+=a,taxi-=b;
                    temp=taxi-petr;
                }
                cout<<petr+a<<endl;
            }
            else{
                while(temp>a){
                    petr+=a,taxi-=b;
                    temp=taxi-petr;
                }
                cout<<taxi<<endl;
            }
        }
    }
}

i pass all the test that the discuss give
but i still get wa at #4
could u give me some new test?

if(a<=b)
---> if(a<b)

but i still get wa at #13

for exanmple try test
1000 2 2000 3

the right answer is 1400
but your prog output 1402

or try this
1 2 12 3

right is 6
but yours is 7

Edited by author 20.03.2008 17:57

Thank u very much!

thanks for 2nd test, it really helpfull)

Thanks a lot...
^_^

// solve
#include <iostream>
using namespace std;

int main()
{
    int a,b,c,d;
    cin>>a>>b>>c>>d;
    while(a< c)
    {
        if(a+b > c)
        {
            a=c;
            break;
        }
        a= a+b;
        if(c <= a)
        {
         break;
        }
        c = c-d;
    }

    cout<<a<<endl;
    return 0;
}