Matr P[35];

Matr power(Matr A, int p) {
    Matr x = IdMatr;
    x.m = x.n = A.m;

    int i = 0;
    while(p > 0) {
        if(p % 2) x = x * P[i];
        i++;
        p /= 2;
    }
    re x;
}

// ....
// in main()...

P[0] = Gen;
    FOR(i,1,34)
        P[i] = P[i-1] * P[i-1];

// ....