再帰的方法で順序表の中で二分検索(半角検索)

int Recurrence_Search_Bin(SSTable ST,KeyType key,int floor,int roof){
    //         ST         key     ，               ，    0
    if(floor > roof) return 0;
    int mid = (floor + roof) / 2;
    if(key == ST.elem[mid].key) return mid;
    else if (key < ST.elem[mid].key) return Recurrence_Search_Bin(ST,key,floor,mid - 1);
    else return Recurrence_Search_Bin(ST,key,mid + 1,roof);
}//Recurrence_Search_Bin