Compilare: main.cpp: In function 'int main()': main.cpp:56:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < ans.length() && !contains1; ++i) ~~^~~~~~~~~~~~~~ main.cpp:23:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("calc.in", "r", stdin); ^ main.cpp:24:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("calc.out", "w", stdout); ^ main.cpp:25:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%hd%lld%s", &CERINTA, &n, s + 1); ^