View Compilation Error

0_0_26455129_17417.cpp: In function 'll work(ll)':
0_0_26455129_17417.cpp:71:12: error: redeclaration of 'll ans'
         ll ans = calc(L - 1) % mod;
            ^
0_0_26455129_17417.cpp:69:12: note: 'll ans' previously declared here
         ll ans = 0;
            ^