数据结构复习代码——基于顺序存储下串的相关操作以及串匹配模式算法的实现

1、基于顺序存储下串的相关操作以及串匹配模式算法的实现

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

#define MAXSTRLEN 20
#define u_char unsigned char

typedef u_char SString[MAXSTRLEN+1];

void InitString(SString S)      //初始化字符串
{
    S[0] = '\0';
}

void StrAssign(SString S,char *str)     //赋值字符串操作
{
    int len = strlen(str);
    for(int i = 0;i<len;i++)
    {
        S[i] = str[i];
    }
    S[len] = '\0';
}

int StrLength(SString S)                //求字符串长度
{
    int len = 0;
    while(*S != '\0')
    {
        len++;
        S++;
    }
    return len;
}

void StrCopy(SString S,SString T)       //复制串操作
{
    int len = StrLength(T);
    for(int i=0;i<len;i++)
    {
        S[i] = T[i];
    }
    S[len] = '\0';
}

bool StrEmpty(SString S)                    //字符串结构判空操作
{
    return S[0] == '\0';
}

int StrCompare(SString S,SString T)         //字符串比较操作
{
    int result = 0;
    while(*S != '\0' || *T != '\0')
    {
        result = *S - *T;
        if(result != 0)
            break;
        S++;
        T++;
    }
    if(result > 0)
        result = 1;
    else if(result <0)
        result = -1;
    return result;
}



void StrConcat(SString T,SString s1,SString s2)         //字符串连接操作
{
    int len1 = StrLength(s1);
    int len2 = StrLength(s2);
    int i;
    /*
    //此处代码较为繁琐，简化后代码在下方
    if(len1+len2<MAXSTRLEN)
    {
        for(i=0;i<len1;i++)
        {
            T[i] = s1[i];
        }
        for(int j=0;j<len2;j++)
        {
            T[i+j] = s2[j];
        }
        T[len1+len2] = '\0';
    }
    else if (len1<MAXSTRLEN)
    {
        for(i=0;i<len1;i++)
        {
            T[i] = s1[i];
        }
        for(int j=0;j<MAXSTRLEN-len1;j++)
        {
            T[i+j] = s2[j];
        }
        T[MAXSTRLEN] = '\0';
    }
    else
    {
        for(int j=0;j<len1;++j)
        {
            T[j] = s1[j];
        }
        T[MAXSTRLEN] = '\0';
    }
    */
    //此处为上述代码简化后，减少了代码长度
    int lenj = 0,length = 0;
    if(len1+len2<MAXSTRLEN)
    {
        length = len1+len2;
        lenj = len2;
    }
    else if(len1 < MAXSTRLEN){
        length = MAXSTRLEN;
        lenj = MAXSTRLEN-len1;
    }
    else{
        length = len1;
        lenj =0;
    }
    for(i=0;i<len1;i++)
    {
        T[i] = s1[i];
    }
    for(int j=0;j<lenj;j++)
    {
        T[i+j] = s2[j];
    }
    T[length] = '\0';

}

void SubString(SString S,SString sub,int pos,int len)       //在S字符串中截取子串
{
    //求子串
    int s_len = StrLength(S);
    if(pos < 0 || pos>=s_len || len <0 || len > s_len)
        return ;
    int j=pos;
    for(int i=0;i<len;i++)
    {
        sub[i] = S[j+i];
    }
    sub[len] = '\0';

}

int StrIndex(SString S,SString T,int pos)
{
    int i =pos;
    int j =0;
    while(S[i]!='\0'&&T[j]!='\0')
    {
        if(S[i]==T[j])
        {
            i++;
            j++;
        }else{
            i = i-j+1;
            j=0;
        }
    }
    if(T[j] == '\0')
        return i-j;
    return -1;

}
//void StrReplace(SString S,SString T,SString V)
void StrInsert(SString S,int pos,SString T)         //在字符串中某位置插入子串
{
    int s_len = StrLength(S);
    int t_len = StrLength(T);
    int i;
    /*
    //
    if(s_len+t_len<=MAXSTRLEN)
    {
        for(i=s_len-1;i>=pos;--i)
        {
            S[i+t_len] = S[i];
        }
        int j = pos;
        for(i=0;i<t_len;++i)
        {
            S[j+i] = T[i];
        }
        S[s_len+t_len] = '\0';
    }
    else if(s_len<MAXSTRLEN)
    {
        t_len = MAXSTRLEN - s_len;
        for(i=s_len-1;i>=pos;--i)
        {
            S[i+t_len] = S[i];
        }
        int j = pos;
        for(i=0;i<t_len;++i)
        {
            S[j+i] = T[i];
        }
        S[s_len+t_len] = '\0';
    }
    */
    if(s_len+t_len<=MAXSTRLEN)
    {
        t_len = StrLength(T);
    }
    else if(s_len+t_len>MAXSTRLEN)
    {
        t_len = MAXSTRLEN - s_len;
    }
    for(i=s_len-1;i>=pos;--i)
    {
        S[i+t_len] = S[i];
    }
    int j = pos;
    for(i=0;i<t_len;++i)
    {
        S[j+i] = T[i];
    }
    S[s_len+t_len] = '\0';
}

void StrDelete(SString S,int pos,int len)       //删除字串
{

    int s_len = StrLength(S);
    if(pos+len>MAXSTRLEN)
    {
        printf("数据输入不合法!!!");
        return;
    }
    for(int i = pos;i<s_len;i++)
    {
        S[i] = S[i+len];
    }
    S[s_len-len] = '\0';
}

void StrClear(SString S)            //清空字符串
{
    S[0] = '\0';
}
void PrintString(SString S)         //输出字符串
{
    printf("%s \n",S);
}

int main()
{
    SString S;
    InitString(S);
    //SString T;
    //InitString(T);
    //char *str = "abcdrh";

    StrAssign(S,"ababcababcab");

    SString T;
    InitString(T);
    StrAssign(T,"abc");

    int index = StrIndex(S,T,0);
    printf("%d \n",index);

    //StrAssign(S,"abcdefhjkl");


    //删除子串操作
    //StrDelete(S,2,3);
    //PrintString(S);

    //插入子串
    //SString T;
    //InitString(T);
    //StrAssign(T,"jjj");
    //StrInsert(S,1,T);
    //PrintString(S);

    //截取子串
    //SString sub;
    //InitString(sub);
    //SubString(S,sub,4,2);
    //PrintString(sub);

    //连接两个字符串部分
    //SString Y;
    //InitString(Y);
    //StrConcat(Y,S,T);
    //PrintString(Y);

    //比较字符串部分
    //int res = StrCompare(S,T);
    //printf("%d \n",res);
    //PrintString(S);

    //复制字符串部分
    //StrCopy(T,S);
    //PrintString(T);
    return 0;
}