Compilare: main.cpp: In function 'int main()': main.cpp:47:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (step + pos < psm[i].size() && psm[i][step + pos] <= poz) { ~~~~~~~~~~~^~~~~~~~~~~~~~~ main.cpp:12:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("zzid.in", "r", stdin) ; ^ main.cpp:13:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("zzid.out", "w", stdout) ; ^ main.cpp:55:42: warning: 'poz' may be used uninitialized in this function [-Wmaybe-uninitialized] std::cout << cnt << ' ' << abs(W - 2 * poz) ; ~~^~~~~~~~~