Compilare: user.cpp: In function ‘long long unsigned int Cost(int, int)’: user.cpp:24:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (CostMatrix[a][a] == -1) ^ user.cpp:26:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (CostMatrix[a + 1][b] == -1) ^ user.cpp:32:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (CostMatrix[a][i] == -1) ^ user.cpp:34:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (CostMatrix[i + 1][b] == -1) ^ user.cpp: In function ‘int main()’: user.cpp:61:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < n; i++) ^ user.cpp:64:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < n; i++) ^ user.cpp:66:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < n; j++) ^ user.cpp:72:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < n; i++) ^