一個有關字符數組大小的疑惑

[cpp]
#include<stdio.h>  
#include<string.h>  
 
char arrays[] = {'a', 'b', 'c', '\0'}; 
char *s = "abc"; 
 
void test() 
{ 
    //arrays和s是相等的,如果arrays[] = {'a','b','c'}則不相等  
    if(strcmp(arrays, s) == 0) 
        printf("arrays == s\n"); 
    printf("%d %d\n", sizeof(arrays), strlen(arrays)); 
    char carray[] = {'a', 'b', 'c', 'd', 'e','f'}; 
    printf("%d %d\n", sizeof(carray), strlen(carray)); 
} 
 
int main() 
{ 
    test(); 
    return 0; 
} 
/*
arrays == s
4 3
6 11
Press any key to continue
}
*/ 

#include<stdio.h>
#include<string.h>

char arrays[] = {'a', 'b', 'c', '\0'};
char *s = "abc";

void test()
{
 //arrays和s是相等的,如果arrays[] = {'a','b','c'}則不相等
 if(strcmp(arrays, s) == 0)
  printf("arrays == s\n");
 printf("%d %d\n", sizeof(arrays), strlen(arrays));
 char carray[] = {'a', 'b', 'c', 'd', 'e','f'};
 printf("%d %d\n", sizeof(carray), strlen(carray));
}

int main()
{
 test();
 return 0;
}
/*
arrays == s
4 3
6 11
Press any key to continue
}
*/為什麼strlen(carray)是11啊???Who can tell me why?