Compilare: user.cpp: In function ‘int main()’: user.cpp:49:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(inputFile.c_str(), "r", stdin); ^ user.cpp:50:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(outputFile.c_str(), "w", stdout); ^ user.cpp:53:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", A + 1); ^ user.cpp:54:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", B + 1); ^ user.cpp:70:18: warning: ‘h2’ may be used uninitialized in this function [-Wmaybe-uninitialized] h2 = (h2 * BASE2 + B[i]) % MOD2; ^ user.cpp:69:18: warning: ‘h1’ may be used uninitialized in this function [-Wmaybe-uninitialized] h1 = (h1 * BASE1 + B[i]) % MOD1; ^