Compilare: main.cpp: In function 'int main()': main.cpp:51:9: warning: unused variable 'n' [-Wunused-variable] int n,i,k,cnt=0; ^ main.cpp:51:11: warning: unused variable 'i' [-Wunused-variable] int n,i,k,cnt=0; ^ main.cpp:51:13: warning: unused variable 'k' [-Wunused-variable] int n,i,k,cnt=0; ^ main.cpp:51:15: warning: unused variable 'cnt' [-Wunused-variable] int n,i,k,cnt=0; ^~~ main.cpp:48:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("next.in","r",stdin); ^ main.cpp:49:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("next.out","w",stdout); ^