Compilare: user.cpp: In function ‘int nap(double)’: user.cpp:29:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=v.size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:65:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<v.size();) ^ user.cpp:49:15: warning: unused variable ‘k’ [-Wunused-variable] int i,j,n,k=0,prev=-1,s=0; ^ user.cpp:49:19: warning: unused variable ‘prev’ [-Wunused-variable] int i,j,n,k=0,prev=-1,s=0; ^ user.cpp:47:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trapez.in","r",stdin); ^ user.cpp:48:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trapez.out","w",stdout); ^ user.cpp:51:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:54:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &p.x,&p.y); ^