Compilare: user.cpp: In function ‘int main()’: user.cpp:8:10: warning: NULL used in arithmetic [-Wpointer-arith] while(a!=NULL&&i<=10000) ^ user.cpp:5:17: warning: unused variable ‘n’ [-Wunused-variable] int c=0,l=0,i=0,n; ^ user.cpp:3:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] {freopen ("text.in","r",stdin); ^ user.cpp:4:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("text.out","w",stdout); ^ user.cpp:7:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&a); ^ user.cpp:14:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&a); ^ user.cpp:17:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&a); ^