2018-03-10 无穷常数的设置

[感谢大佬的博客](http://blog.csdn.net/kiritow/article/details/52094163)

const int INF = 0x3f3f3f3f;
const int NINF = -INF -1;  
const int NINF = 0xc0c0c0c0;
//memset直接对连续的内存进行无穷大初始化
memset(blockptr,0x3f,blocksize);
//使用memset对连续内存进行无穷小初始化
memset(blockptr,0xc0,blocksize);