sizeof vs strlen

    char c1[] = { 'a','b','\0','d','e' };
    char c2[] = "hello";
    char *c3 = "hello";

    sizeof(c1) = 5;
    strlen(c1) = 2;

    sizeof(c2) = 6;
    strlen(c2) = 5;

    sizeof(c3) = 4;
    strlen(c3) = 5;