View Compilation Error

0_0_26596966_876.cpp: In function 'int main()':
0_0_26596966_876.cpp:15:12: error: 'ch' was not declared in this scope
         if(ch[i]==max)
            ^
0_0_26596966_876.cpp:15:19: error: 'max' was not declared in this scope
         if(ch[i]==max)
                   ^