View Compilation Error

0_0_33565622_8545.cpp: In function 'ull read()':
0_0_33565622_8545.cpp:11:9: error: expected initializer before 'ans'
     ull ans=0;
         ^
0_0_33565622_8545.cpp:18:13: error: 'ans' was not declared in this scope
             ans+=fi[i];
             ^
0_0_33565622_8545.cpp:21:12: error: 'ans' was not declared in this scope
     return ans;
            ^