Compilare: user.cpp: In function ‘void bfs(int, int)’: user.cpp:66:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = 0; k < edge[i].size(); k++) ^ user.cpp: In function ‘int isFlow()’: user.cpp:277:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = 0; k < edge[i].size(); k++) ^ user.cpp:303:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = 0; k < L0edge[i].size(); k++) ^ user.cpp:323:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = 0; k < L0edge[i].size(); k++) ^ user.cpp:330:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = 0; k < L0invedge[i].size(); k++) ^ user.cpp:378:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = L0idx[node]; k < L0edge[node].size(); k++) ^ user.cpp:388:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = L0invidx[node]; k < L0invedge[node].size(); k++) ^ user.cpp: In function ‘void readInputData()’: user.cpp:23:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(filein, "r", stdin); ^ user.cpp:25:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &N, &M, &G); ^ user.cpp:35:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &i, &j, &c); ^ user.cpp: In function ‘void writeOutputData(double)’: user.cpp:49:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(fileout, "w", stdout); ^