View Compilation Error

0_0_13079196_30203.cpp: In function 'int main()':
0_0_13079196_30203.cpp:29:18: error: 'a' was not declared in this scope
         if(tower[a][b][c])//网上的，出口是墙，表这样
                  ^
0_0_13079196_30203.cpp:29:21: error: 'b' was not declared in this scope
         if(tower[a][b][c])//网上的，出口是墙，表这样
                     ^
0_0_13079196_30203.cpp:29:24: error: 'c' was not declared in this scope
         if(tower[a][b][c])//网上的，出口是墙，表这样
                        ^