Compilare: user.cpp: In function ‘void write()’: user.cpp:69:9: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ user.cpp: In function ‘void read()’: user.cpp:8:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("calcul.in", "r", stdin); ^ user.cpp:10:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s1, maxN, stdin); ^ user.cpp:12:27: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s2, maxN, stdin); ^ user.cpp:14:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &c); ^ user.cpp: In function ‘void write()’: user.cpp:70:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("calcul.out", "w", stdout); ^