Compilare: user.cpp: In function ‘int main()’: user.cpp:30:15: warning: unused variable ‘j’ [-Wunused-variable] int x, t, i, j; ^ user.cpp:31:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen (InFile, "r", stdin); ^ user.cpp:32:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen (OutFile, "w", stdout); ^ user.cpp:33:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &t); ^ user.cpp:37:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1; i<=49; i++) scanf ("%d", &x), v[x]++; ^