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Improve solution for 2024 day 4 part 1

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SebastianStork 2024-12-13 15:52:36 +01:00
parent 65f1dac915
commit 943db1881c
1 changed files with 57 additions and 39 deletions
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96
2024/day-04/main.cpp
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@ -13,50 +13,68 @@ vector<string> readInput()
return lines;
}
bool wordIsXmas(const string &word)
{
return word == "XMAS" || word == "SAMX";
}
int xmasCountAt(const vector<string> &matrix, const size_t rowIndex, const size_t colIndex)
{
const size_t numberOfRows = matrix.size();
const size_t numberOfCols = matrix[0].size();
int xmasCount = 0;
// Horizontal check
if (colIndex + 3 < numberOfCols) {
string horizontalWord = matrix[rowIndex].substr(colIndex, 4);
xmasCount += wordIsXmas(horizontalWord);
}
// Vertical check
if (rowIndex + 3 < numberOfRows) {
string verticalWord;
for (size_t i = 0; i <= 3; i++) {
verticalWord += matrix[rowIndex + i][colIndex];
}
xmasCount += wordIsXmas(verticalWord);
}
// Down-diagonal check
if (rowIndex + 3 < numberOfRows && colIndex + 3 < numberOfCols) {
string downDiagonalWord;
for (size_t i = 0; i <= 3; i++) {
downDiagonalWord += matrix[rowIndex + i][colIndex + i];
}
xmasCount += wordIsXmas(downDiagonalWord);
}
// Up-diagonal check
if (rowIndex + 3 < numberOfRows && colIndex + 3 < numberOfCols) {
string upDiagonalWord;
for (size_t i = 0; i <= 3; i++) {
upDiagonalWord += matrix[rowIndex + (3 - i)][colIndex + i];
}
xmasCount += wordIsXmas(upDiagonalWord);
}
return xmasCount;
}
int main()
{
int numberOfOccurences = 0;
const vector<string> matrix = readInput();
const size_t numberOfRows = matrix.size();
const size_t numberOfCols = matrix[0].size();
// Horizontal
for (size_t rowIndex = 0; rowIndex < matrix.size(); rowIndex++) {
for (size_t colIndex = 0; colIndex < matrix[0].size() - 3; colIndex++) {
const string nextWord = matrix[rowIndex].substr(colIndex, 4);
if (nextWord == "XMAS" || nextWord == "SAMX") {
numberOfOccurences++;
}
int numberOfXmasOccurrences = 0;
for (size_t rowIndex = 0; rowIndex < numberOfRows; rowIndex++) {
for (size_t colIndex = 0; colIndex < numberOfCols; colIndex++) {
numberOfXmasOccurrences += xmasCountAt(matrix, rowIndex, colIndex);
}
}
// Vertical
for (size_t colIndex = 0; colIndex < matrix[0].size(); colIndex++) {
for (size_t rowIndex = 0; rowIndex < matrix.size() - 3; rowIndex++) {
string nextWord;
for (size_t i = 0; i <= 3; i++) {
nextWord += matrix[rowIndex + i][colIndex];
}
if (nextWord == "XMAS" || nextWord == "SAMX") {
numberOfOccurences++;
}
}
}
// Diagonal
for (size_t rowIndex = 0; rowIndex < matrix.size() - 3; rowIndex++) {
for (size_t colIndex = 0; colIndex < matrix[0].size() - 3; colIndex++) {
string nextWord1, nextWord2;
for (size_t i = 0, j = 3; i <= 3; i++, j--) {
nextWord1 += matrix[rowIndex + i][colIndex + i];
nextWord2 += matrix[rowIndex + j][colIndex + i];
}
if (nextWord1 == "XMAS" || nextWord1 == "SAMX") {
numberOfOccurences++;
}
if (nextWord2 == "XMAS" || nextWord2 == "SAMX") {
numberOfOccurences++;
}
}
}
cout << "Number of XMAS occurences: " << numberOfOccurences << endl;
// Part one
cout << "Number of XMAS occurrences: " << numberOfXmasOccurrences << endl;
}