Compilare: user.cpp: In function ‘void Radix_sort(int)’: user.cpp:13:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < n; ++i) ^ user.cpp:20:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 1; j <= a[i][0]; ++j) ^ user.cpp:23:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (p < bp) ^ user.cpp: In function ‘int main()’: user.cpp:31:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < n; ++i) ^ user.cpp:36:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < n; i += 10) ^