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Check-in [70a16d5d32]

Overview
Comment:202404 2nd star
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SHA3-256: 70a16d5d32fbf149554b5be030658d14dd2a607267ce4e6515da5896253f4558
User & Date: nnz on 2024-12-04 11:56:38
Original Comment: day 4, part 2 solved
Other Links: manifest | tags
Context
2024-12-04
12:02
changed way of summing a boolean check-in: 4609a146ec user: nnz tags: trunk
11:56
202404 2nd star check-in: 70a16d5d32 user: nnz tags: trunk
10:51
202404 1st star check-in: 0fa98a442c user: nnz tags: trunk
Changes
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Modified aoc2024.c from [3d58482423] to [bd078583fe].

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    if (masat(data, size, row, col,  0, -1)) finds++;
    if (masat(data, size, row, col,  0, +1)) finds++;
    if (masat(data, size, row, col, +1, -1)) finds++;
    if (masat(data, size, row, col, +1,  0)) finds++;
    if (masat(data, size, row, col, +1, +1)) finds++;
    return finds;
}

static bool Xmasat(char *data, unsigned size, unsigned row, unsigned col) {
    unsigned tmp = 0;
    if (data[rcmap(size, row, col)] != 'A') return false;
    if (data[rcmap(size, row-1, col-1)] == 'M') tmp |= 1;
    if (data[rcmap(size, row-1, col-1)] == 'S') tmp |= 2;
    if (data[rcmap(size, row-1, col+1)] == 'M') tmp |= 4;
    if (data[rcmap(size, row-1, col+1)] == 'S') tmp |= 8;
    if (data[rcmap(size, row+1, col+1)] == 'M') tmp |= 1;
    if (data[rcmap(size, row+1, col+1)] == 'S') tmp |= 2;
    if (data[rcmap(size, row+1, col-1)] == 'M') tmp |= 4;
    if (data[rcmap(size, row+1, col-1)] == 'S') tmp |= 8;
    return tmp == 15;
}

void aoc202404(char *data, size_t len) {
    (void)len; // unused argument
    // assume data is well-formatted and has the same number of rows and columns
    unsigned size = strchr(data, '\n') - data;
    #if 0 // check assumption
    printf("data has %u cols, first three rows start with %c%c, %c%c, and %c%c.\n",
          size, data[0], data[1],
          data[1*(size+1)], data[1*(size+1)+1],
          data[2*(size+1)], data[2*(size+1)+1]);
    printf("ends with %c%c.\n", data[(size-1)*(size+1) + size-2], data[(size-1)*(size+1)+size-1]);
    printf("data has %u cols, first three rows start with %c%c, %c%c, and %c%c.\n",
          size, data[rcmap(size, 0, 0)], data[rcmap(size, 0, 1)],
          data[rcmap(size, 1, 0)], data[rcmap(size, 1, 1)],
          data[rcmap(size, 2, 0)], data[rcmap(size, 2, 1)]);
    printf("ends with %c%c.\n", data[rcmap(size, size-1, size-2)], data[rcmap(size, size-1, size-1)]);
    #endif
    unsigned xmascount = 0;
    unsigned xmascount = 0, Xmascount = 0;
    for (unsigned row = 0; row < size; row++) {
        for (unsigned col = 0; col < size; col++) {
            xmascount += xmasat(data, size, row, col);
            if ((1 <= row) && (row < size - 1) && (1 <= col) && (col < size - 1)) {
                Xmascount += Xmasat(data, size, row, col);
            }
        }
    }
    printf("XMAS appears %u times in the little Elf's word search.\n", xmascount);
    printf("X-MAS appears %u times in the little Elf's word search.\n", Xmascount);
}

void aoc202403(char *data, size_t len) {
    (void)len; // unused argument
    unsigned sumproducts = 0, sumproducts2 = 0, term[2];
    char *rest = data;
    char *doleft = data;
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