字符串

c++ 中
    常量字符串存储在单独额内存区域，
        当其赋给指针时，指针指向字符串首地址
        当将其存入数组，是将字符串的每个值依次存入数组，此时数组首地址与常量字符串首地址不同

#include <stdio.h>
#include <string.h>
int main() {
	
	char str1[] = "hello world";
	char str2[] = "hello world";
	
	char *str3 = "hello world";
	char *str4 = "hello world";
	
	if(str1 == str2) {
		printf("str1 and str2 are the same.\n");
	} else {
		printf("str1 and str2 are not same.\n");
	}
	printf("%d\n", strcmp(str1, str2));
	
	if(str3 == str4) {
		printf("str3 and str4 are the same.\n");
	} else {
		printf("str3 and str4 are not same.\n");
	}
	printf("%d\n", strcmp(str3, str4));
	return 0;
}

//output
str1 and str2 are not same.
0
str1 and str2 are the same.
0

== 同 java，比较地址
strcmp 同 java equal， 比较内容