Avoid using system(). Since you are using Windows, use the Console API do clear the screen:
Code:
#include <windows.h>
...
void clearscreen(void)
{
HANDLE hConsole;
COORD coord = {0, 0};
CONSOLE_SCREEN_BUFFER_INFO csbi;
DWORD dwConsoleSize, dwWriten;
hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
GetConsoleScreenBufferInfo(hConsole, &csbi);
dwConsoleSize = csbi.dwSize.X * csbi.dwSize.Y;
FillConsoleOutputCharacter(hConsole, (TCHAR)' ',
dwConsoleSize, coord, &dwWriten);
FillConsoleOutputAttribute(hConsole, csbi.wAttributes,
dwConsoleSize, coord, &dwWriten);
SetConsoleCursorPosition(hConsole, coord);
}
And, on Windows you can use Sleep() to wait N milisseconds.