计时操作 "t" to left brace, "c" equals 0 : "t" plus 1 , 1 , right brace , "f" Subscript, "t" , Baseline to left brace, "c" equals 0 : "f" Subscript, "t" , Baseline plus .0 5 , 0 , right brace , "x" Subscript, 0 , Baseline to 2.5 left brace, "c" equals 1 , right bracet→c=0:t+1,1,ft→c=0:ft+.05,0,x0→2.5c=1
