C语言数据结构——串

C语言数据结构——串

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

#define MAXSIZE 100

typedef char ElemType;

typedef struct{
	ElemType data[MAXSIZE];
	int length;
}String;

String* initString()
{
	String *s = (String*)malloc(sizeof(String));
	s->length = 0;
	return s;
}
//初始化串

int strAssign(String *s,char *chars)
{
	int len = strlen(chars);
	if(len > MAXSIZE)
	{
		printf("FULL.\n");
		return 0;
	}
	for(int i = 0;i < len;i++)
	{
		s->data[i] = chars[i];
	}
	s->length = len;
	return 1;
}
//把字符数组赋值给串

void strPrint(String *s)
{
	for(int i = 0;i < s->length;i++)
	{
		printf("%c",s->data[i]);
	}
	printf("\n");
}
//输出串

int strLength(String *s)
{
	return s->length;
}
//获取串长

int strCompare(String *s1,String *s2)
{
	int min = s1->length < s2->length ? s1->length : s2->length;
	for(int i = 0;i < min;i++)
	{
		if(s1->data[i] != s2->data[i])
		{
			return s1->data[i] - s2->data[i];
		}
	}
	return s1->length - s2->length;
}
//比较两个串

int concat(String *s3,String *s1,String *s2)
{
	if(s1->length + s2->length > MAXSIZE)
	{
		printf("FULL.\n");
		return 0;
	}
	int index = 0;
	for(int i = 0;i < s1->length;i++)
	{
		s3->data[index++] = s1->data[i];
	}
	for(int i = 0;i < s2->length;i++)
	{
		s3->data[index++] = s2->data[i];
	}
	s3->length = index;
	return 1;
}
//串连接

int subString(String *sub,String *s,int pos,int len)
{
	if(pos < 1 || pos > s->length || len < 0 || pos + len - 1 > s->length)
	{
		return 0;
	}
	for(int i = 0;i < len;i++)
	{
		sub->data[i] = s->data[pos - 1 + i];
	}
	sub->length = len;
	return 1;
}
//求子串

int indexOf(String *s,String *t)
{
	for(int i = 0;i <= s->length - t->length;i++)
	{
		int j = 0;
		while(j < t->length && s->data[i + j] == t->data[j])
		{
			j++;
		}
		if(j == t->length)
		{
			return i + 1;
		}
	}
	return 0;
}
//查找子串第一次出现的位置

int main()
{
	String *s1 = initString();
	String *s2 = initString();
	String *s3 = initString();
	String *sub = initString();
	strAssign(s1,"Hello");
	strAssign(s2,"World");
	concat(s3,s1,s2);
	strPrint(s3);
	printf("%d\n",strLength(s3));
	subString(sub,s3,2,4);
	strPrint(sub);
	printf("%d\n",indexOf(s3,s2));
	return 0;
}