View Compilation Error

0_0_21642510_13985.cpp: In function 'int main()':
0_0_21642510_13985.cpp:11:21: error: 'scanf' was not declared in this scope
     scanf( "%d", &t );
                     ^
0_0_21642510_13985.cpp:19:35: error: 'sort' was not declared in this scope
         sort( pos+1, pos+n+1, cmp );
                                   ^
0_0_21642510_13985.cpp:28:41: error: 'printf' was not declared in this scope
                 printf( "%d", a[pos[j]] );
                                         ^
0_0_21642510_13985.cpp:31:42: error: 'printf' was not declared in this scope
                 printf( " %d", a[pos[j]] );
                                          ^
0_0_21642510_13985.cpp:34:22: error: 'printf' was not declared in this scope
         printf( "\n" );
                      ^