00000000000000000000000000000000 = 0
00000000000000000000000000000001 = 1
00000000000000000000000000000010 = 2
00000000000000000000000000000011 = 3
...
00000000000000000000000011111111 = 255
...
01111111111111111111111111111111 = 2147483647
10000000000000000000000000000000 = -2147483648
...
11111111111111111111111111111101 = -3
11111111111111111111111111111110 = -2
11111111111111111111111111111111 = -1

11111111111111111111111111111111の下位8ビット = 00000000000000000000000011111111 = 255