View Compilation Error

0_0_17075619_20396.cpp: In function 'void init()':
0_0_17075619_20396.cpp:16:29: error: 'memset' was not declared in this scope
     memset(Dfs,0,sizeof(Dfs));
                             ^
0_0_17075619_20396.cpp: In function 'int main()':
0_0_17075619_20396.cpp:78:13: error: 'i' was not declared in this scope
         for(i=1;i<=n;i++)
             ^