Compilare: user.cpp: In function ‘void read()’: user.cpp:35:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &m, &source, &dest); ^ user.cpp:40:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp:41:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &cap[x][y], &cost[x][y]); ^ user.cpp: In function ‘int main()’: user.cpp:160:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in", "r", stdin); ^ user.cpp:161:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out", "w", stdout); ^