View Compilation Error

0_0_32631685_1459.cpp: In function 'int main()':
0_0_32631685_1459.cpp:24:14: error: 's' was not declared in this scope
 #define mid (s+e>>1)
              ^
0_0_32631685_1459.cpp:58:25: note: in expansion of macro 'mid'
                     int mid=(l+r)/2;
                         ^
0_0_32631685_1459.cpp:24:16: error: 'e' was not declared in this scope
 #define mid (s+e>>1)
                ^
0_0_32631685_1459.cpp:58:25: note: in expansion of macro 'mid'
                     int mid=(l+r)/2;
                         ^