View Compilation Error

0_0_20711637_6541.cpp: In function 'int main()':
0_0_20711637_6541.cpp:12:8: error: 'i' was not declared in this scope
   for( i = 0 ; i < n - 1; i ++ ) {
        ^
0_0_20711637_6541.cpp:21:8: error: 'i' was not declared in this scope
   for( i = 0 ; i < n ; i ++ )
        ^