View Compilation Error

0_0_39748351_11255.c:2:1: error: unknown type name 'using'
    2 | using namespace std;
      | ^~~~~
0_0_39748351_11255.c:2:17: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'std'
    2 | using namespace std;
      |                 ^~~
0_0_39748351_11255.c:4:1: error: unknown type name 'bool'
    4 | bool st[N];//因数之和表，初始为0，有就设为1
      | ^~~~
0_0_39748351_11255.c:2:1: note: 'bool' is defined in header '<stdbool.h>'; did you forget to '#include <stdbool.h>'?
    1 | #include<stdio.h>
  +++ |+#include <stdbool.h>
    2 | using namespace std;
0_0_39748351_11255.c:4:6: error: variably modified 'st' at file scope
    4 | bool st[N];//因数之和表，初始为0，有就设为1
      |      ^~
0_0_39748351_11255.c: In function 'init':
0_0_39748351_11255.c:11:1: error: unknown type name 'bool'
   11 | bool flag=1;//哨兵法
      | ^~~~
0_0_39748351_11255.c:11:1: note: 'bool' is defined in header '<stdbool.h>'; did you forget to '#include <stdbool.h>'?