text: enum { N = 100 };
  
  double A[N][N], B[N];
  
  int main() {
    int I, J;
    double S = 0;
    for (I = 0; I < N; ++I)
      for (J = 0; J < N; ++J)
        A[I][J] = I * 2.3 * J;
    for (I = 1; I < N; ++I)
      B[I] =  A[I - 1][I - 1];
    B[0] = 1;
    for (I = 0; I < N; ++I)
      for (J = 0; J < N; ++J)
        S = S + A[I][J] * B[J];
    return S;
  }
  