Compilare: main.cpp: In function 'bool Letter(char)': main.cpp:14:81: warning: suggest parentheses around '&&' within '||' [-Wparentheses] 14 | return (letter >= 'a' && letter <= 'z') || (letter >= 'A' && letter <= 'Z') && letter != ' '; | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:24:31: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare] 24 | for(int index = 0 ; index < strlen(text); index) | ~~~~~~^~~~~~~~~~~~~~ main.cpp:24:47: warning: for increment expression has no effect [-Wunused-value] 24 | for(int index = 0 ; index < strlen(text); index) | ^~~~~ main.cpp:21:9: warning: unused variable 'index' [-Wunused-variable] 21 | int index = 0; | ^~~~~