Compilare: user.c: In function ‘main’: user.c:27:1: warning: format ‘%s’ expects argument of type ‘char *’, but argument 3 has type ‘char (*)[101]’ [-Wformat=] fscanf(file1, "%s", &number); ^ user.c:29:1: warning: implicit declaration of function ‘strlen’ [-Wimplicit-function-declaration] len = strlen(number); ^ user.c:29:7: warning: incompatible implicit declaration of built-in function ‘strlen’ [enabled by default] len = strlen(number); ^ user.c:8:8: warning: unused variable ‘i’ [-Wunused-variable] int T, i, tail, len, period[100] = ^ user.c:23:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(file1, "%d", &T); ^ user.c:27:7: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(file1, "%s", &number); ^