foo.cc: In function 'void in(int&)':
foo.cc:7:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(x=0;c>='0'&&c<='9';c=getchar())x=(x<<3)+(x<<1)+(c^'0');x*=fl;}
  ^~~
foo.cc:7:61: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
  for(x=0;c>='0'&&c<='9';c=getchar())x=(x<<3)+(x<<1)+(c^'0');x*=fl;}
                                                             ^
foo.cc: In function 'int main()':
foo.cc:13:66: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
 for(rint i=1,k=n-(1<<j)+1;i<=k;i++)f[i][j]=mx(f[i][j-1],f[i+(1<<j-1)][j-1]);
                                                                 ~^~

自豪的采用jd5进行评测(github.com/masnn/jd5)