unit: sectors

/dev/sda1 : start=     2048, size= 39060453, Id=83
/dev/sda2 : start= 39062502, size=  1048576, Id=82
/dev/sda3 : start=        0, size=        0, Id= 0
/dev/sda4 : start=        0, size=        0, Id= 0
