/in/foo.c:1:10: error: #include expects "FILENAME" or <FILENAME>
 #include _CRT_SECURE_NO_WARNINGS
          ^~~~~~~~~~~~~~~~~~~~~~~
/in/foo.c: In function 'main':
/in/foo.c:29:1: warning: implicit declaration of function 'pintf' [-Wimplicit-function-declaration]
 pintf("%d", sum);
 ^~~~~
/in/foo.c:8:5: warning: variable 'ren' set but not used [-Wunused-but-set-variable]
 int ren[20] = { 0 };
     ^~~