Compilare: main.cpp: In function 'int main()': main.cpp:57:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sortnet.in", "r", stdin); ^ main.cpp:58:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sortnet.out", "w", stdout); ^ main.cpp:62:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] int n, m; scanf("%d%d\n", &n, &m); ^ main.cpp:66:42: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] int x, y; scanf("<%d,%d> ", &x, &y); --x, --y; ^ main.cpp:70:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^