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| + + +---+ + + + +---+ + +---+ +---+ + + +---+---+ + + +---+---+ + | | | | | | | | | | |XXX| | | | | |XXX| | | | |XXX| | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ Step 15 Step 16 Step 17 Step 18 Step 19 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | | | | | | | | | | | | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | | | | | | | | | |XXX| | |XXX| | | | | | + + + + + + + + + + +---+ + +---+ + + +---+ + | | | | | | | | | | |XXX| | |XXX| | | |XXX| | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | |XXX| | | | | |XXX| | | | | | | | | | | | |XXX| | | + +---+---+ + + +---+ +---+ + +---+ + + + +---+ + + + +---+ + + | | |XXX| | | | | |XXX| | | | | | | | | | | | | | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ Step 20 Step 21 Step 22 Step 23 Step 24 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+---+ +---+ + + +---+ + + +---+ + + +---+ + + | | |XXX| | | | | | | | | | | | | | | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | | | | | | | |XXX| | | |XXX| | | |XXX| | | |XXX| | | | + + + + + + + + +---+ + + +---+ + + +---+ + + +---+ + + + | | | | | | | | |XXX| | | |XXX| | | |XXX| | | |XXX| | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ Step 30 Step 31 Step 32 Step 33 Step 34 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | | | | | | | | | | | | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | | | |XXX| | | | |XXX| | | | | | | | | | +---+ + + +---+ + + + +---+ + + + + + + + + + |XXX| | | |XXX| | | | |XXX| | | | | | | | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ |XXX| | | | | | | | | | | | | | | | |XXX| | | |XXX| | | +---+ + + + +---+ + + + +---+ + + + +---+ +---+ + +---+---+ + + | | | | | | | | | | | | | | | | | |XXX| | | |XXX| | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ Step 35 Step 36 Step 37 Step 38 Step 39 +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ | | | | | | |XXX|XXX| | | |XXX|XXX| | | |XXX| +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+ +---+ | | | | |XXX|XXX| | | | | | | | | | | | | | | + + + + +---+---+ + + +---+---+ + + +---+---+ + + +---+---+---+ + | | | | | | | | | | | | | | | | | |XXX| | +---+---+---+---+ + +---+---+ + +---+---+ + +---+---+ + +---+---+ |XXX|XXX| | | | | | | | | | | | | | | | | | | +---+---+ + + +---+---+ + + +---+---+ + + +---+---+ + + +---+---+ + + | | | | | | | | | | | | | | | | | | | | | | | | | +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ +---+---+---+---+ Step 40 Step 41 Step 42 Step 43 Step 44 +---+---+---+---+ +---+---+---+---+ 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