20999+1=21000
53399+1=53400
52399+1=52400
2000-1=1999
65999+1=66000
200000-1=199999
318000-1=317999
345999+1=346000
765000-1=764000
20999+1=21000
53399+1=53400
20999+1=21000
52399+1=52400
2000-1=1999
65999+1=66000
200000-1=199999
318000-1=317999
345999+1=346000
765000-1=764000