POJ-1006 Biorhythms

#include <iostream>
using namespace std;

int main()
{
    int p, e, i, d, caseno = 1;
    const int CIRCLE[3] = {23,28,33};
    while (true)
    {
        cin>>p>>e>>i>>d;
        if (p == -1 && e == -1 && i == -1 && d == -1)
            break;

        int testday = d + 1;
        int largestIndex;
        int largestDay;

        // 记录第一次遇到高峰的日期testday，和这个高峰是属于哪个项目
        while (true)
        {
            if ((testday-p) % CIRCLE[0] == 0)
            {
                largestIndex = 0;
                largestDay = p;
                break;
            }
            else if ((testday-e) % CIRCLE[1] == 0)
            {
                largestIndex = 1;
                largestDay = e;
                break;
            }
            else if ((testday-i) % CIRCLE[2] == 0)
            {
                largestIndex = 2;
                largestDay = i;
                break;
            }
            else 
            {
                testday++;
            }            
        }

        // 寻找三个高峰的日期
        while (true)
        {
            if ((largestIndex == 0 || (testday-p) % CIRCLE[0] == 0) &&
                (largestIndex == 1 || (testday-e) % CIRCLE[1] == 0) &&
                (largestIndex == 2 || (testday-i) % CIRCLE[2] == 0))
            {
                int resultday = testday - d;
                cout<<"Case "<<caseno++<<": the next triple peak occurs in "<< resultday <<" days."<<endl;
                break;
            }

            testday += CIRCLE[largestIndex];
        }

    }

    return 0;
}