Compilare: user.cpp: In function ‘int main()’: user.cpp:39:45: warning: operation on ‘k1’ may be undefined [-Wsequence-point] v1[++k1] = v1[k1 - 1] + cs[i - 1] * p1; ^ user.cpp:64:45: warning: operation on ‘k2’ may be undefined [-Wsequence-point] v2[++k2] = v2[k2 - 1] + cd[i + 1] * p1; ^ user.cpp:18:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("slide.in", "r", stdin); ^ user.cpp:19:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("slide.out", "w", stdout); ^ user.cpp:21:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ /tmp/ccjbr8ic.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.