Compilare: user.cpp: In function ‘int main()’: user.cpp:64:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i <= N; i++) { ^ user.cpp:81:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j == N - 1) ^ user.cpp:108:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j == N - 1) ^ user.cpp:60:16: warning: unused variable ‘pozl’ [-Wunused-variable] long i, j, pozl; ^ user.cpp:61:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.in", "r", stdin); ^ user.cpp:62:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.out", "w", stdout); ^ user.cpp:63:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lu %lu %lu", &N, &L, &U); ^ user.cpp:65:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lu", &t); ^