View Compilation Error

0_0_13355426_28.cpp:1:9: error: #include expects "FILENAME" or <FILENAME>
 #include
         ^
0_0_13355426_28.cpp:2:9: error: #include expects "FILENAME" or <FILENAME>
 #include
         ^
0_0_13355426_28.cpp:3:9: error: #include expects "FILENAME" or <FILENAME>
 #include
         ^
0_0_13355426_28.cpp: In function 'int main()':
0_0_13355426_28.cpp:62:19: error: 'scanf' was not declared in this scope
     scanf ("%d",&T);
                   ^
0_0_13355426_28.cpp:66:37: error: 'memset' was not declared in this scope
         memset (head,-1,sizeof(head));
                                     ^
0_0_13355426_28.cpp:86:35: error: 'printf' was not declared in this scope
                 printf ("%d\n",k-1);
                                   ^
0_0_13355426_28.cpp:88:51: error: 'printf' was not declared in this scope
                 printf ("%d\n",(k - maxn)*2+maxn-1);
                                                   ^