Compilare: user.cpp: In function ‘void solve()’: user.cpp:56:9: warning: unused variable ‘i’ [-Wunused-variable] int i, j, d, sum = 0, dif = inf; ^ user.cpp:56:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, d, sum = 0, dif = inf; ^ user.cpp: In function ‘void read()’: user.cpp:17:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("centru.in", "r", stdin); ^ user.cpp:18:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:24:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x1, &y1); ^ user.cpp: In function ‘void write()’: user.cpp:70:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("centru.out", "w", stdout); ^