View Compilation Error

0_0_39673599_25167.cpp: In function 'int main()':
0_0_39673599_25167.cpp:30:36: error: 'j' was not declared in this scope
   30 |                 f[i][1] = f[i - 1][j - 1][0] + dw[i];
      |                                    ^
0_0_39673599_25167.cpp:34:9: error: expected ',' or ';' before 'cout'
   34 |         cout << ans << endl;
      |         ^~~~