Compilare: user.cpp: In function ‘int main()’: user.cpp:29:15: warning: unused variable ‘k’ [-Wunused-variable] int i, j, k, x, y, jump, w, n, m, pend, val; ^ user.cpp:26:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mayonaka.in", "r", stdin); ^ user.cpp:27:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mayonaka.out", "w", stdout); ^ user.cpp:31:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &n, &m); ^ user.cpp:35:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(BUFF); ^ /tmp/ccDQFLhy.o: In function `main': user.cpp:(.text.startup+0xb5): warning: the `gets' function is dangerous and should not be used.