Compilare: user.cpp: In function ‘int main()’: user.cpp:42:12: warning: unused variable ‘i’ [-Wunused-variable] int T, i, per, size; ^ user.cpp:42:15: warning: unused variable ‘per’ [-Wunused-variable] int T, i, per, size; ^ user.cpp:42:20: warning: unused variable ‘size’ [-Wunused-variable] int T, i, per, size; ^ user.cpp:43:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("prefix.in", "r", stdin); ^ user.cpp:44:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ user.cpp: In function ‘int compute()’: user.cpp:21:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &SIR[0]); ^ user.cpp:22:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &SIR[1]); ^ user.cpp:23:5: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=2; SIR[i-1] != '\n'; ++i, scanf("%c", &SIR[i-1])) { ^