View Compilation Error

0_0_31218103_2938.cpp:22:16: error: '::main' must return 'int'
 long long main()
                ^
0_0_31218103_2938.cpp: In function 'int main()':
0_0_31218103_2938.cpp:34:3: error: expected ';' before 'for'
   for(long long i=0;i<n-1;i++)
   ^
0_0_31218103_2938.cpp:34:21: error: 'i' was not declared in this scope
   for(long long i=0;i<n-1;i++)
                     ^