View Compilation Error

0_0_33850392_10407.cpp: In function 'void get_sg()':
0_0_33850392_10407.cpp:24:17: error: 'MAXN' was not declared in this scope
         int vis[MAXN];
                 ^
0_0_33850392_10407.cpp:25:16: error: 'vis' was not declared in this scope
         memset(vis, 0, sizeof(vis));
                ^