Compilare: user.cpp: In function ‘int main()’: user.cpp:18:18: warning: unused variable ‘k’ [-Wunused-variable] int i, j, n, k; ^ user.cpp:15:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.in", "r", stdin); ^ user.cpp:16:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.out", "w", stdout); ^ user.cpp:20:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(BUFF); n = strlen(BUFF); ^ /tmp/ccKmKuFd.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.