Compilare: main.cpp: In function 'int main()': main.cpp:16:15: warning: unused variable 'j' [-Wunused-variable] int n,k,i,j; ^ main.cpp:14:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("kperm.in","r",stdin); ^ main.cpp:15:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("kperm.out","w",stdout); ^ main.cpp:17:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&k); ^