int main()
{
int a = 3;//a = 011二进制位（下同）
int b = 5;//b = 101
a = a ^ b;//a = 110 ^二进制按位异或，相同为0，反之为1
b = a ^ b;//b = 011
a = a ^ b;//a = 101完成交换；
printf("a = %d\nb = %d\n", a, b);
//a = a + b;//a=和，b是原来的b
//b = a - b;//b得到原来的a
//a = a - b;//a得到原来的b
////int 有最大值,2147483647
//INT_MAX;
//printf("a = %d\nb = %d\n", a, b);
//printf("%d\n", INT_MAX);
return 0;
}