X17276: Diagonals creixents

#include <iostream>
#include <vector>
using namespace std;


typedef vector<int> Row;
typedef vector<Row> Matrix;


//Pre: Llegeix una sequencia de valors
//Post: Omple la matriu amb aquests;
void read_matrix(Matrix& M) {
    int f = M.size();
    int c = M[0].size();
    for (int i = 0; i < f; ++i) {
        for (int j = 0; j < c ; ++j) {
            cin >> M[i][j];
        }
    }
}

//Pre: Consulta les diagonals de la matriu a partir del punt a,b
//Post: Retorna true si i nomes si esta ordenat creixentment
bool increasing_d(const Matrix& M, int a, int b) {
    int f = M.size();
    int c = M[0].size();
    //dalt-dreta
    int i = a-1, j = b+1, comp = M[a][b];
    while (i >= 0 && j < c) {
        if (M[i][j] > comp) comp = M[i][j];
        else return false;
        --i;
        ++j;
    }
    //dalt-esquerra
    i = a-1, j = b-1, comp = M[a][b];
    while (i >= 0 && j >= 0) {
        if (M[i][j] > comp) comp = M[i][j];
        else return false;
        --i;
        --j;
    }
    //baix-esquerra
    i = a+1, j = b-1, comp = M[a][b];
    while (i < f && j >= 0) {
        if (M[i][j] > comp) comp = M[i][j];
        else return false;
        ++i;
        --j;
    }
    //baix-dreta
    i = a+1, j = b+1, comp = M[a][b];
    while (i < f && j < c) {
        if (M[i][j] > comp) comp = M[i][j];
        else return false;
        ++i;
        ++j;
    }
    return true;
}

int main() {
    int f, c;
    while (cin >> f >> c) { //Tamany matriu
        Matrix M(f, Row(c));
        read_matrix(M);
        cin >> f >> c; //Posicio inicial
        if (increasing_d(M, f, c)) cout << "si" << endl;
        else if (not increasing_d(M, f, c)) cout << "no" << endl;
    }
}

//JosepRivaille