foo.cc: In function 'int main()':
foo.cc:19:74: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   19 |                  if(l > 0) dp[l][r] = dp[l - 1][r] + v[i][l] * (2 << len - 1);
      |                                                                      ~~~~^~~
foo.cc:20:94: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   20 |                  if(r > 0) dp[l][r] = max(dp[l][r], dp[l][r - 1] + v[i][m - r+1] * (2 << len - 1));
      |                                                                                          ~~~~^~~

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