View Compilation Error

0_0_39822179_28315.c:1:1: error: unknown type name 'using'
    1 | using namespace std;
      | ^~~~~
0_0_39822179_28315.c:1:17: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'std'
    1 | using namespace std;
      |                 ^~~
0_0_39822179_28315.c:6:5: error: variably modified 'f' at file scope
    6 | int f[N][N];
      |     ^
0_0_39822179_28315.c:6:5: error: variably modified 'f' at file scope