foo.cc: In function 'long long int dfs(int, int, int, int, long long int)':
foo.cc:10:43: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   10 |         int maxnn=max(f[l][x-1],f[r-(1<<x - 1)+1][x-1]);
      |                                         ~~^~~
foo.cc: In function 'int main()':
foo.cc:38:56: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   38 |                         f[j][i]=max(f[j][i-1],f[j+(1<<i-1)][i-1]);
      |                                                       ~^~
foo.cc:42:41: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   42 |         int maxn=max(f[1][x-1],f[n-(1<<x-1)+1][x-1]);
      |                                        ~^~
foo.cc: In function 'long long int dfs(int, int, int, int, long long int)':
foo.cc:23:1: warning: control reaches end of non-void function [-Wreturn-type]
   23 | }
      | ^

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