Member Avatar for Labdabeta

I am making a diplomacy tool, for the board game diplomacy. I need to make a map of each territory. I have a 75 #define MAP_"NAME" lines but I don't know how to set them to a mask value that can be checked since I don't know any 75-bit or larger datastructures that can be declared as datatype=0x<lots of digits>. How do I make a new datatype of X-bytes to store this that can be defined as such? Any help would be appreciated!!!

  • 2 Contributors
  • 2 Replies
  • 218 Views
  • 8 Hours Discussion Span
  • Latest Post Latest Post by Labdabeta

Dani AI

Generated

Quick expert addendum referencing 's pointer to fixed and dynamic bit containers and 's choice to store indices 0–74. For a 75-territory Diplomacy map the practical options are: a fixed-size bit container (std::bitset<75>) or a dynamic bit container (Boost dynamic_bitset or similar), a compact custom two-word mask, or simple index lists (vector<int>). Bit containers give O(1) membership tests and extremely fast set ops (bitwise AND/OR). Index lists are often simpler for sparse holdings and easy to iterate or serialize as lists.

A small, safe custom mask that fits 75 bits and exposes set/test/bitwise ops:

#include <cstdint>
#include <cstddef>

struct Mask75 {
    uint64_t lo;   // bits 0..63
    uint16_t hi;   // bits 64..74 (low 11 bits used)

    Mask75(): lo(0), hi(0) {}

    void set(std::size_t i) {
        if (i < 64) lo |= (uint64_t(1) << i);
        else          hi |= (uint16_t(1) << (i - 64));
    }

    void reset(std::size_t i) {
        if (i < 64) lo &= ~(uint64_t(1) << i);
        else          hi &= ~(uint16_t(1) << (i - 64));
    }

    bool test(std::size_t i) const {
        return (i < 64) ? (lo & (uint64_t(1) << i)) != 0
                        : (hi & (uint16_t(1) << (i - 64))) != 0;
    }

    Mask75 operator|(const Mask75& o) const {
        Mask75 r; r.lo = lo | o.lo; r.hi = hi | o.hi; return r;
    }
    Mask75 operator&(const Mask75& o) const {
        Mask75 r; r.lo = lo & o.lo; r.hi = hi & o.hi; return r;
    }
};

Notes and pitfalls: C++ integer literals cannot directly hold 75-bit hex constants, so initialize bit containers from strings or parse hex into words. Avoid std::vector<bool> (proxy reference semantics). Keep a stable mapping from territory name to bit index (enum or const array) so saved games remain consistent. For sparse data where iteration dominates, index lists (vector<int> per country) are compact and easy. For frequent set algebra, prefer std::bitset/ dynamic bitset or the custom two-word approach above (fast, compact, simple to serialize). Watch shifts: never shift by >= the operand width (undefined behavior), and define endianness explicitly when writing raw bytes.

Recommended Answers

All 2 Replies

Member Avatar for Labdabeta

Thanks, I decided to go with integers from 0-74 and use dynamic arrays to pass multiple countries, thanks anyways.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.