prog.c:2:1: warning: return type defaults to 'int' [-Wimplicit-int]
main()
^
prog.c: In function 'main':
prog.c:5:2: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'printf'
printf("%d\n",i);
^
prog.c:6:14: error: 'j' undeclared (first use in this function)
printf("%d",j);
^
prog.c:6:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:4:6: warning: unused variable 'i' [-Wunused-variable]
int i,j
^