It depends on the number of bits in the operating system. Everyone's computer is different. It seems that it is generally a 32-bit or 64-bit system now. If it is a 32-bit system, the system will automatically allocate four bytes of int, and the range of values is -2 to+2 to minus 1, which is signed, and to 4294967296 for unsigned systems. If it is a 64-bit machine, 8 bytes are an int, and the range is similar to the above.