12.23

1. Error correction:
idea: array out-of-bounds problem

(a)、
void test1()
{
    char string[10];
    char *str1 = "0123456789";//超出数组范围了，10个外加上一个\0,11个
    strcpy(string, str1);
}
(b)、
void test2()
{
    char string[10], str1[10];
    for (i=0; i<10; i++)//int i;
    {
        str1[i] = 'A';
    }
    strcpy(string, str1);//strcpy此时不能用于数组之间的赋值
}
(c)、
void test3(char *str)//char *str1
{
    char string[10];
    if (strlen(str1)<=10)
    {
        strcpy(string, str1);
    }
}   

2. Find a player: 2 badminton teams compete, each with 3 players, and each player only competes once. Team A consists of A, B, and C, and Team B consists of X, Y, and Z. Someone inquired about the competition list, A said that he did not compare with X, and C said that he did not compare with X and Z. Program to find the list of three teams of players.

Idea: Just follow the conditions

百度得:
#include <stdio.h>  
#define a d[0]  
#define b d[1]  
#define c d[2]  

int main(void)  
{  
    char d[]="zyx",temp;  
    int i=0;  

    while(!(a!='x'&&c!='x'&&c!='z'))  
    {  
        i++;  
        if(i%2){temp=a;a=b;b=temp;}       
        if(i%3){temp=b;b=c;c=temp;}  
        else{temp=a;a=c;c=temp;}  
        puts(d);  
    }  

    printf("a=%c b=%c c=%c\n",a,b,c);  
    return 0;  
}  

3. Use C language to replace substrings in strings, return 0 if successful, and -1 if failed. For example, in the string "ABCDEFG", replace "BCD" with the substring "9527", and the result becomes : "A9527EFG"
function prototype:
int str_replace(char str, char replaced_str, char *new_str)

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

int str_replace(char *str, char * replaced_str, char *new_str)
{

}
int main(void)
{

    return 0;
}