Compilare: main.cpp: In function 'll calc(std::__cxx11::string)': main.cpp:25:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) ~^~~~~~~~~ main.cpp: In function 'll after(std::__cxx11::string, int, int)': main.cpp:40:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(;dec<s.size();dec++,ans++) ~~~^~~~~~~~~ main.cpp: In function 'void solve()': main.cpp:61:24: warning: NULL used in arithmetic [-Wpointer-arith] if(str[i]==NULL) break; ^~~~ main.cpp:64:16: warning: converting to non-pointer type 'char' from NULL [-Wconversion-null] str[i]=NULL; ^~~~ main.cpp:56:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:59:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s",str); ^ main.cpp:67:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s",str); ^ main.cpp: In function 'int main()': main.cpp:112:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("rebus.in", "r", stdin); ^ main.cpp:113:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("rebus.out", "w", stdout); ^ main.cpp:118:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^