Compilare: user.cpp: In function ‘int main()’: user.cpp:10:25: warning: NULL used in arithmetic [-Wpointer-arith] for(i=0; ch[i]!=NULL; i++){ ^ user.cpp:11:28: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if((ch[i]>='a' && ch[i]<='z' || ch[i]>='A' && ch[i]<='Z') && !(ch[i+1]>='a' && ch[i+1]<='z' || ch[i+1]>='A' && ch[i+1]<='Z')){ ^ user.cpp:11:89: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if((ch[i]>='a' && ch[i]<='z' || ch[i]>='A' && ch[i]<='Z') && !(ch[i+1]>='a' && ch[i+1]<='z' || ch[i+1]>='A' && ch[i+1]<='Z')){ ^