Compilare: user.cpp: In function ‘int main()’: user.cpp:50:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < strlen(s)){ ^ user.cpp:47:24: warning: unused variable ‘k’ [-Wunused-variable] int val = 0, sign, k = 0, i, nr = 0, sum = 0; ^ user.cpp:45:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expresie2.in","r",stdin); ^ user.cpp:46:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expresie2.out","w",stdout); ^ user.cpp:48:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", s); ^