/in/foo.c:11:1: warning: return type defaults to 'int' [-Wimplicit-int]
 main()
 ^~~~
/in/foo.c: In function 'main':
/in/foo.c:15:3: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   for(j=2;j<=s/2;j++)
   ^~~
/in/foo.c:18:4: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
    printf("%d",m);
    ^~~~~~