Compilare: user.cpp: In function ‘int main()’: user.cpp:110:9: warning: unused variable ‘i’ [-Wunused-variable] int i, j, a, b, c; ^ user.cpp:110:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, a, b, c; ^ user.cpp:110:15: warning: unused variable ‘a’ [-Wunused-variable] int i, j, a, b, c; ^ user.cpp:110:18: warning: unused variable ‘b’ [-Wunused-variable] int i, j, a, b, c; ^ user.cpp:110:21: warning: unused variable ‘c’ [-Wunused-variable] int i, j, a, b, c; ^ user.cpp: In function ‘void cit(int&)’: user.cpp:14:96: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] while(!isdigit(buff[pos])) if(++pos == buff_size) fread(buff, 1,buff_size, stdin), pos = 0; ^ user.cpp:19:73: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(++pos == buff_size) fread(buff, 1, buff_size, stdin), pos = 0; ^ user.cpp: In function ‘int main()’: user.cpp:107:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] { freopen("dijkstra.out","w",stdout); ^ user.cpp:108:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.in","r",stdin); ^