Wrong Answer
/in/foo.cc: In function 'int main()':
/in/foo.cc:20:35: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
f[i][j]=max(f[i][j-1],f[i+(1<<j-1)][j-1]);
~^~
/in/foo.cc: In function 'int main()':
/in/foo.cc:20:35: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
f[i][j]=max(f[i][j-1],f[i+(1<<j-1)][j-1]);
~^~