View Compilation Error

0_0_27457038_20894.cpp: In function 'LL Solve(LL, LL)':
0_0_27457038_20894.cpp:58:16: error: 'c' was not declared in this scope
  rvis[rn]=true;c
                ^
0_0_27457038_20894.cpp:61:22: error: 'last' was not declared in this scope
  for(LL d=2LL;d<=n;d=last+1)
                      ^