How to check if any row of a matrix contains all 'A's?

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I've been trying to do this, but the problem is that there's always something wrong or missing with the final result. I have a lot of if statements and I wanted to see if it is possible to reduce it by using a for loop.

char matrix[3][3] = {
    {'A','A','A'},{'B','A','B'},{'C','A','C'}
};

if (matrix[0][0] == 'A' && matrix[0][1] == 'A' && matrix[0][2] == 'A') {
            cout << "Found!" << endl;
        }

There are a lot more if statements and I didn't put it here because it's the same thing just different index.

I tried to do a for loop like this,

for (int i = 0; i < matrix[0][2]; i++) {
            if (matrix[0][0] == matrix[0][1] && matrix[0][0] == matrix[0][2])
                cout << "Found!" << endl;
            break;
        }

This looks more organized compared to almost 20 lines of if statements, but it still missing some parts. For example in the array [0][1] and [1][1] and [2][1] all have the character 'A'. How can implement this into the for loop to print out the message when the same character appears in the same line vertically or horizontally.

if-statement multidimensional-array for-loop arrays c++
1 Answers

You can use standard algorithms to express this conveniently:

if (std::any_of(std::begin(matrix), std::end(matrix), 
                [](auto const & row) {
                    return std::all_of(std::begin(row), std::end(row), 
                                       [](char c) {
                                           return c == 'A';
                                       });
                }))
{
    std::cout << "Found";
}

From C++20, this becomes a little easier to read and write:

namespace rs = std::ranges;
if (rs::any_of(matrix, [](auto const & row) {
        return rs::all_of(row, [](char c) {
            return c == 'A';
        });
    }))
{
    std::cout << "Found";
}

Here's a demo

user_83728530
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