View Compilation Error

0_0_18280199_5869.cpp: In function 'int main()':
0_0_18280199_5869.cpp:13:3: error: 'else' without a previous 'if'
   else if(r<=1) 
   ^
0_0_18280199_5869.cpp:17:6: error: 'else' without a previous 'if'
      else if(l==r||l==r-1) 
      ^