Compilare: user.cpp: In function ‘int main()’: user.cpp:116:15: warning: unused variable ‘i’ [-Wunused-variable] int n, t, i, v1, v2; ^ user.cpp: In function ‘int ch(int)’: user.cpp:62:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:113:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hprob.in", "r", stdin); ^ user.cpp:114:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hprob.out", "w", stdout); ^ user.cpp:122:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:124:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %lf %lf %lf", &n, &p1, &p2, &p3); ^