1_000_000
1__000000
1000000_
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0.0001
0.000_1
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0._0001
0.0001_

1e+23
1_e+23
1__e+23
1e_+23

1e+23
1e+_23
1e+23_

0x
0xffff
0xff_ff
0x_ffff
0x__ffff
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0b
0b01_0000__0000
0b01_
0b_01
0b__01

3.141_592_653_589_793
96_485.332_89
6.022_140_857e+23

0o
0o7_77
0o700_
0o_700
0o__700