View Compilation Error

0_0_18266123_30259.cpp: In function 'void push_up(int, int, int)':
0_0_18266123_30259.cpp:42:9: error: redeclaration of 'int mid'
     int mid = (l+r)>>1;
         ^
0_0_18266123_30259.cpp:39:9: note: 'int mid' previously declared here
     int mid = (l+r)>>1;
         ^