View Compilation Error

0_0_28726705_15046.cpp: In function 'int main()':
0_0_28726705_15046.cpp:24:9: error: 'i' was not declared in this scope
    for( i=1;i<=n;i++)
         ^
0_0_28726705_15046.cpp:43:9: error: 'i' was not declared in this scope
    for( i=n-2;i>=1;i++)
         ^