Compilare: user.cpp: In function ‘void solve()’: user.cpp:67:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(L[cnt]<l[cnt].size()) ^ user.cpp: In function ‘void read()’: user.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); ^ user.cpp:18:60: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1;i<=n;i++) scanf("%d%d",&a[i].val,&a[i].col); ^ user.cpp: In function ‘int main()’: user.cpp:77:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("placute.in","r",stdin); ^ user.cpp:78:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("placute.out","w",stdout); ^