哈希表（csp-s模拟测试53 v）

struct map_hash{       struct node{
   int to,n;double val;int len;}e[31000001];       int tot=0;        int head[MAXN];int len=0;       double &operator[](int state){              int st=state*len%mod+1;              for(int i=head[st];i;i=e[i].n){                  if(e[i].to==state&&e[i].len==len)                  return e[i].val;              }              e[++tot].to=state;              e[tot].val=-1.0;               e[tot].len=len;                           e[tot].n=head[st];              head[st]=tot;              return e[tot].val;       }}f;

二元组加和和比较大小

struct node{    int fir;int sec;    friend node operator +(node a,node b){        return (node){a.fir+b.fir,a.sec+b.sec};    }};inline node minn(node a,node b){    if(a.fir==b.fir)return a.sec