View Compilation Error

0_0_37417801_14041.cpp: In function 'int main()':
0_0_37417801_14041.cpp:20:12: error: 'i' was not declared in this scope
     }FenMu[i]/FenMu[i-1]*FenZi[i-1]
            ^
0_0_37417801_14041.cpp:22:27: error: 'N' was not declared in this scope
     while(~scanf("%I64d",&N))
                           ^
0_0_37417801_14041.cpp:30:31: error: 'FM' was not declared in this scope
            LL factor = gcd(FZ,FM);
                               ^