cmpsc330hw2/main.cpp

#include <algorithm>
#include <iostream>
#include <map>
#include <sstream>
#include <vector>

#define pt cout <<
#define pter cerr <<
#define nl "\n"
#define in cin >>

using namespace std;

// -------- START RAII HELPERS--------

unsigned long allocatedMem = 0;

void *alloc(size_t size) {
    void *ptr = malloc(size);
    if (ptr == nullptr) {
        pter "Memory allocation failed" << nl;
        return nullptr;
    }
    allocatedMem += 1;
    return ptr;
}

void dealloc(void *ptr) {
    if (ptr) free(ptr);
    allocatedMem -= 1;
}

bool assert_alloc() {
    return !allocatedMem;
}

// -------- END RAII HELPERS--------

struct Move {
    char player;
    int moveX;
    int moveY;
};

struct Moves {
    int x;
    int y;
    vector<Move> moves;
};

bool isValidPlayer(char c) {
    return c >= 'A' && c <= 'Z' && c != 'X';
}

Moves serialize(const string &s) {
    // TODO: add check for impossible board sizes

    Moves result;
    istringstream iss(s);
    iss >> result.x >> result.y;
    result.x <<= 1;
    result.y <<= 1;

    string player;
    int x, y;
    while (iss >> player >> x >> y) {
        if (player == "END") break;
        if (!isValidPlayer(player[0])) {
            string err = "Invalid player: " + player;
            throw invalid_argument(err);
        }
        Move move;
        move.player = player[0];
        move.moveX = x;
        move.moveY = y;
        result.moves.push_back(move);
    }

    return result;
}

char **allocBoard(int x, int y) {
    char **board = static_cast<char **>(alloc(x * sizeof(char *)));
    for (int i = 0; i < x; ++i) {
        board[i] = static_cast<char *>(alloc(y * sizeof(char)));
    }
    return board;
}

void initBoard(char **board, int x, int y) {
    for (int i = 0; i < x; ++i) {
        for (int j = 0; j < y; j++) {
            board[i][j] = (j & 1 || i & 1) ? ' ' : '.';
        }
    }
}

char **allocAndInitBoard(int x, int y) {
    char **board = allocBoard(x, y);
    initBoard(board, x, y);
    return board;
}

void deallocBoard(char **board, int x) {
    for (int i = 0; i < x; ++i) {
        dealloc(board[i]);
    }
    dealloc(board);
}

void printBoard(char **board, int x, int y) {
    for (int i = 0; i < x; ++i) {
        for (int j = 0; j < y; ++j) {
            pt board[i][j];
        }
        pt nl;
    }
}

char toLowerCase(char c) {
    return c | 32;
}

int normalize(char c) {
    return toLowerCase(c) - 'a';
}

void swap(pair<char, int> *a, int i, int j) {
    pair<char, int> temp = a[i];
    a[i] = a[j];
    a[j] = temp;
}

void bubbleSort(pair<char, int> *a) {
    for (int i = 0; i < 25; i++) {
        for (int j = 0; j < 25 - i; j++) {
            if (a[j].second > a[j + 1].second)
                swap(a, j, j + 1);
        }
    }
}


void printScores(int *points) {
    pair<char, int> *arr = static_cast<pair<char, int> *>(alloc(26 * sizeof(pair<char, int>)));
    for (int i = 0; i < 26; i++) {
        pair<char, int> p;
        p.first = static_cast<char>(i + 'a');
        p.second = points[i];
        arr[i] = p;
    }

    bubbleSort(arr);

    int prev = -1;

    for (int i = 0; i < 26; i++) {
        if (arr[i].second != -1) {
            pt arr[i].first << ": " << arr[i].second << " boxes" << (
                i == 25 || prev == arr[i].second ? " (win)\n" : nl);
            prev = arr[i].second;
        }
    }

    dealloc(arr);
}

bool isValidMove(int x, int y) {
    return (x & 1) != (y & 1);
}

void addPoint(
    int *points,
    char **board,
    int x,
    int y,
    char player
) {
    if (board[x][y] == ' ') {
        if (points[normalize(player)] == -1) {
            points[normalize(player)] = 1;
        } else {
            points[normalize(player)]++;
        }
        board[x][y] = player;
    }
}

void solveVertical(
    int moveX,
    int moveY,
    char **board,
    int *points,
    int x,
    int y,
    char player
) {
    // TODO: fix ambiguity:
    //  -
    // |
    //  -
    // in the condition above, we do not know what to do at the end of the board

    // need to check for x-1, x+1, y-1, y+1

    // check for any box below current move
    if (moveX < x - 3 && board[moveX + 2][moveY] != ' ' && board[moveX + 1][moveY - 1] != ' ') {
        int rightEdge = moveY == y - 1 ? 1 : board[moveX + 1][moveY + 1] != ' ';
        if (rightEdge) {
            addPoint(points, board, moveX + 1, moveY, player);
        }
    }

    // check for any box above current move
    if (moveX > 1 && board[moveX - 2][moveY] != ' ' && board[moveX - 1][moveY - 1] != ' ') {
        int rightEdge = moveY == y - 1 ? 1 : board[moveX - 1][moveY + 1] != ' ';
        if (rightEdge) {
            addPoint(points, board, moveX - 1, moveY, player);
        }
    }
}

void solveHorizontal(
    int moveX,
    int moveY,
    char **board,
    int *points,
    int y,
    char player
) {
    if (moveY) {
        if (moveY == y - 1) {
            if (board[moveX][moveY - 2] != ' ' && (
                    board[moveX + 1][moveY - 1] != ' ' && board[moveX - 1][moveY - 1] != ' ')) {
                addPoint(points, board, moveX, moveY - 1, player);
            }
        } else {
            if (board[moveX][moveY - 2] != ' ' || board[moveX][moveY + 2] != ' ') {
                if (board[moveX + 1][moveY - 1] != ' ' && board[moveX - 1][moveY - 1] != ' ') {
                    addPoint(points, board, moveX, moveY - 1, player);
                }
                if (board[moveX + 1][moveY + 1] != ' ' && board[moveX - 1][moveY + 1] != ' ') {
                    addPoint(points, board, moveX, moveY + 1, player);
                }
            }
        }
    } else {
        if (board[moveX][moveY + 2] != ' ' && (board[moveX + 1][moveY + 1] != ' ' && board[moveX - 1][moveY + 1] !=
                                               ' ')) {
            addPoint(points, board, moveX, moveY + 1, player);
        }
    }
}

void solve(Moves moves, char **board) {
    int *points = static_cast<int *>(alloc(26 * (sizeof(int))));
    for (int i = 0; i < 26; i++) {
        points[i] = -1;
    }

    for (int i = 0; i < moves.moves.size(); i++) {
        Move move = moves.moves[i];

        int moveX = move.moveX;
        int moveY = move.moveY;
        char player = move.player;

        if (!isValidMove(moveX, moveY)) {
            pt "Invalid move by: " << player << " at (x, y): (" << moveX << ", " << moveY << ")" << nl;
            board[moveX][moveY] = 'X';
            printBoard(board, moves.x, moves.y);

            printScores(points);
            pt "Exiting.." << nl;
            return;
        }

        board[moveX][moveY] = toLowerCase(player);

        // TODO:
        if (moveX % 2 == 0 && moveY % 2 == 1) {
            solveVertical(moveX, moveY, board, points, moves.x, moves.y, player);
        } else if (moveX % 2 == 1 && moveY % 2 == 0) {
            solveHorizontal(moveX, moveY, board, points, moves.y, player);
        } else {
            pt "Invalid move by: " << player << " at (x, y): (" << moveX << ", " << moveY << ")" << nl;
            board[moveX][moveY] = 'X';
            printBoard(board, moves.x, moves.y);

            printScores(points);
            pt "Exiting.." << nl;
            return;
        }
    }

    printBoard(board, moves.x, moves.y);
    printScores(points);
    dealloc(points);
}

int init(char *fileName) {
    // --- IO START ---
    FILE *inp = fopen(fileName, "r");
    if (inp == nullptr) {
        pter "File not found" << nl;
        return 1;
    }

    fseek(inp, 0L, SEEK_END);
    const long sz = ftell(inp);
    fseek(inp, 0L, SEEK_SET);

    char *fileInpPtr = static_cast<char *>(alloc(sz + 1 * sizeof(char)));
    fileInpPtr[sz] = '\0';

    for (int i = 0; i < sz; ++i) {
        fscanf(inp, "%c", &fileInpPtr[i]);
    }
    // --- IO END ---

    // --- ALGORITHM START ---
    Moves moves = serialize(fileInpPtr);
    char **board = allocAndInitBoard(moves.x, moves.y);
    solve(moves, board);
    // --- ALGORITHM END ---

    // --- CLEANUP START ---
    dealloc(fileInpPtr);
    deallocBoard(board, moves.x);
    fclose(inp);

    if (!assert_alloc()) {
        pter "Memory leak detected" << nl;
        return 1;
    }
    // --- CLEANUP END ---
    return 0;
}

int main(int argc, char **argv) {
    if (argc < 2) {
        pter "No input file provided" << nl;
        pter "Usage: dotsandboxes /path/to/input.txt" << nl;
        return 1;
    }

    try {
        return init(argv[1]);
    } catch (const invalid_argument &e) {
        pter e.what() << nl;
        return 1;
    }
}