// Since C23 bool, true and false are keywords.
const char *name = "Alex";
bool nameExists = strlen(name) > 0;
//nameExists is true
int number = 7;
bool isTen = number == 10;
//isTen is false
// Any nonzero value turns into true, that is 1.
bool fromNumber = 42;
//fromNumber is true
// printf has no bool format: pick a word (with %d, true prints as 1)
printf("nameExists is %s\n", nameExists ? "true" : "false");
printf("isTen is %s\n", isTen ? "true" : "false");
printf("fromNumber is %s\n", fromNumber ? "true" : "false");