poj 1658 Eva's Problem

#include <iostream>using namespace std;int main(){    int tc, num[5], tmp[3];    cin >> tc;    while (tc--)    {        cin >> num[0] >> num[1] >> num[2] >> num[3];          tmp[0] = num[1] - num[0];        tmp[1] = num[2] - num[1];        tmp[2] = num[3] - num[2];        if (tmp[0] == tmp[1] && tmp[1] == tmp[2])        {            num[4] = num[3] + tmp[0];            for (int i = 0; i < 5; i++)            {                if (i)                   cout << " ";                cout << num[i];            }             cout << endl;        }        else        {            num[4] = (num[3] * num[3])/num[2];            for (int i = 0; i < 5; i++)            {                if (i)                   cout << " ";                cout << num[i];            }             cout << endl;        }    }        system("pause");}