/in/foo.c: In function 'main':
/in/foo.c:15:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("%d",a,sum);
            ^~~~
/in/foo.c:7:5: warning: 'x' is used uninitialized in this function [-Wuninitialized]
     for(a=1;a<=x; a++)
     ^~~