Compilare: user.c: In function ‘main’: user.c:16: warning: format ‘%ld’ expects type ‘long int *’, but argument 2 has type ‘int *’ user.c:18: warning: format ‘%ld’ expects type ‘long int *’, but argument 2 has type ‘int *’ user.c:12: warning: unused variable ‘last’ user.c:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result user.c:16: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:21: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result user.c:23: warning: ignoring return value of ‘gets’, declared with attribute warn_unused_result user.c:25: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result /tmp/ccsUJPeV.o: In function `main': user.c:(.text+0xbb): warning: the `gets' function is dangerous and should not be used.