/in/foo.cc: In function 'int main()':
/in/foo.cc:7:5: error: 'cin' was not declared in this scope
     cin >> n >> m;
     ^~~
/in/foo.cc:16:54: error: 'abs' was not declared in this scope
             dp[i][j] = dp[i-1][j+i] + dp[i-1][abs(j-i)];
                                                      ^
/in/foo.cc:20:9: error: 'cout' was not declared in this scope
         cout << dp[n][m] / 2 << endl;
         ^~~~
/in/foo.cc:20:33: error: 'endl' was not declared in this scope
         cout << dp[n][m] / 2 << endl;
                                 ^~~~
/in/foo.cc:22:9: error: 'cout' was not declared in this scope
         cout << dp[n][m] << endl;
         ^~~~
/in/foo.cc:22:29: error: 'endl' was not declared in this scope
         cout << dp[n][m] << endl;
                             ^~~~
/in/foo.cc:8:9: warning: unused variable 'sum' [-Wunused-variable]
     int sum = 0;
         ^~~