174
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It does not matter what you put after this. This will not be read.

the song is 43.467 seconds long.
43.467 ~ 43.50
43.467 is close to 43.50 seconds (or 172 + 2 quater seconds)

Figure out how many quarter seconds are there in 43.50 seconds
43 * 4 =  172
0.50/0.25 = 2;

172 + 2 = 174

Once you figure out how many quarter seconds there are in your song you put that number as the first line. 
Note: it can not have any decimal points.