Compilare: user.cpp: In function ‘int main()’: user.cpp:91:18: warning: unused variable ‘j’ [-Wunused-variable] int n, m, i, j, np; ^ user.cpp:89:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nuke.in", "r", stdin); ^ user.cpp:90:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nuke.out", "w", stdout); ^ user.cpp:93:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ user.cpp:96:57: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n", &sold[i].first, &sold[i].second); ^ user.cpp: In member function ‘void BOMB::read(int)’: user.cpp:17:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(ln); ^ /tmp/ccqywB20.o: In function `main': user.cpp:(.text.startup+0xf8): warning: the `gets' function is dangerous and should not be used.