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#include <stdio.h>
#include <bios.h>

int yesno()
{
	int scan;

	do{
		scan = (bioskey(0) >> 8) & 0xff;
	} while((scan != 0x15) && (scan != 0x31));
	if(scan == 0x15)
		return 1;
	return 0;
}
.

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