China DOS Union

Turbo C environment, program overview:
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while (no key pressed) {
display string
sleep(5 minutes) / delay(5 minutes)
clear string
change screen coordinates
}
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Requirement: When no key is pressed, refresh the string every 5 minutes. And respond to key presses at any time (exit when a key is pressed).

Now the situation is that although there is a key pressed, it must wait until the 5 minutes are up before it can exit.