prog.c: In function ‘main’:
prog.c:5: warning: format ‘%d’ expects type ‘int *’, but argument 2 has type ‘int’
prog.c:6: error: ‘c’ undeclared (first use in this function)
prog.c:6: error: (Each undeclared identifier is reported only once
prog.c:6: error: for each function it appears in.)
prog.c:5: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result