一硝:(HHV(HIGH,9)+LLV(LOW,9))/2,colorred;
二黄:(HHV(HIGH,26)+LLV(LOW,26))/2,coloryellow;
硝酸钾:=ma(c,3);
硫磺:=ma(硝酸钾,5);
木炭:=ma(硝酸钾,60);
三木炭:=3*木炭-2*硫磺;
aa:=cross(二黄,三木炭);
bb:=cross(一硝,二黄);
DRAWTEXT(bb,二黄,'火'),colorred;
DRAWTEXT(aa,二黄,'黑火药'),colorwhite;
