静态串及其基本操作（C语言实现）

 

 BCPL  BasicCombinedProgammingLanguage即C语言实现

静态串实现

#include <stdio.h>
#include <stdlib.h>
//打印字符串
void displayStr(const char *string){
    while((*string)){
        printf("%c",*string);
        string++;
    }
    printf("/n");   
}    
//返回字符串长度
int strlen(const char *string){
    int i = 0;
    while(string[i]){
        i++;
    }
    return i;
}
//复制
char* strcpy1(char * string1, const char* string2)
{
char* s1 = string1;
while(*s1++ = *string2++);
return string1;
}
// 比较两字符串是否相等
int strcmp(const char *string1,const char *string2){
    while(*string1 == *string2 && (*string2)){
        string1++;
        string2++;
    }
    if(*string1 == *string2 && (!*string1)){
        return 1;//equal
    }   
    else if(*string1 && (!*string2)){
        return 0; //string1 is longer
    }
    else{
        return 0;//string2 is longer
    }
       
}
//连接
char* strcat1(char *string1, char *string2){
    int len = 0;
    char* newstring;
    char* s1 = string1;
    char* s2 = string2;
    while(*string1++)
    len++;
    while(*string2++)
    len++;
    string1 = (char*)malloc(len * sizeof(char));
    if(!string1)
    exit(-1);
    newstring = string1;
   
    while(*s1)
    *string1++ = *s1++;
    while(*s2)
    *string1++ = *s2++;
    *string1 = '/0';
    return newstring;   
}
//查找某个字符的位置
int posChar(const char* str, char letter){
    int i = 0;
    if(*str){
        while(*str != letter){
            str++;
            ++i;
        }
        return i;
    }
    else
    {
        printf("Sorry, your string is empty!/n");
        return 0;
    }         
}
//查找某一字符在字符串中出现的次数
int strcnt(const char* str, char letter){
    int cnt = 0;
    while(*str){
        if(*str == letter){
            cnt++;
        }
        str++;   
    }
    return cnt; 
}

main(){
    char string1[] = "abcdc";
    char string2[] = "abcdefafvd";
    char* string3;
    int len,pos,count; 
    printf("the string1 is : ");
    displayStr(string1);
    printf("the string2 is : ");
    displayStr(string2);
    //get the string1 length
    len = strlen(string2);
    printf("the length of string2 is %d/n",len);
   
    //compare the two strings
    if(strcmp(string1,string2)){
        printf("string1 equals string2./n");
    }
    else{
        printf("Not equal!/n");
    }
    //find the 'm' in the string1
    pos = posChar(string1,'d');
    if(!pos || pos > len){
        printf("Sorry, the d does not exist in string1/n");
    }
    else{
        printf("the position of d is %d/n",pos);
    } 
    //某一字符在字符串中出现的次数
    count = strcnt(string1,'c');
    printf("the c appears %d times in the string1./n",count);  
    //连接字符串
    printf("after catenate : %s/n",strcat1(string1,string2)); 
    //字符串复制
    printf("after copy : %s/n",strcpy1(string1,string2));   
    getchar();
}