问题

以下是已翻译的代码部分：

我必须使用一个接受两个字符串和一个整数值的函数，该整数值告诉第二个字符串要插入到第一个字符串的位置。

例如：

String 1 = "I have apple"
String 2 = "an "
position = 6

输出：

String 1 = "I have an apple"

这是我的代码，到目前为止：

```cpp
#include <iostream>
using namespace std;

const int SIZE=102;

void insertString(char str1[ ],char str2[ ],int position);

int main()
{
    char str1[SIZE], str2[SIZE];
    int position,i=0,j=0;
    
    cout<<"Enter string 1 of atmost 50 characters:\n";
    cin.getline(str1,SIZE/2);
    
    cout<<"Enter string 2 of atmost 50 characters:\n";
    cin.getline(str2,SIZE/2);
    
    cout<<"Enter Position number where String 2 is to be inserted: ";
    cin>>position;
    
    while(position<0||position>50)
    {
        cout<<"Invalid input. Enter a positive Position number less than 51\n"<<
        "where String 2 is to be inserted: ";
        cin>>position;
    }
    
    insertString(str1,str2,position);
    
    cout<<"Modified string 1: "<<str1<<endl;
    
    system("pause");
    return 0;
}

/*************************************************************************
Definition of function insertString:

This function takes two C-string in form of character arrays and one integer value
as parameters

It inserts String 2 in String 1 on the required position. 

*************************************************************************/

void insertString(char str1[ ],char str2[ ],int position)
{
    char temp[SIZE]; 
    int i,j,countStr2;
    
    for(j=0;j<SIZE&&str2[j]!=0;j++)
        countStr2=j;
        
    for(i=position,j=0;i<SIZE,j<=countStr2; i++,j++)
    {
        temp[i]=str1[i];
        str1[i]=str2[j];
        
    }

}

这个逻辑会覆盖字符串1的一些字符。我应该怎么办？

任何帮助将不胜感激。

<details>
<summary>英文:</summary>

I have to use a function that takes two strings and one integer value that tell the position at which the second string is to be entered in the first. 

For Example:

String 1 = "I have apple"
String 2 = "an "
position = 6,

Output:

String 1 = "I have an apple"

Here's my code, so far:

#include <iostream>
using namespace std;

const int SIZE=102;

void insertString(char str1[ ],char str2[ ],int position);

int main()
{
char str1[SIZE], str2[SIZE];
int position,i=0,j=0;

cout<<"Enter string 1 of atmost 50 characters:\n";
cin.getline(str1,SIZE/2);

cout<<"Enter string 2 of atmost 50 characters:\n";
cin.getline(str2,SIZE/2);

cout<<"Enter Position number where String 2 is to be inserted: ";
cin>>position;

while(position<0||position>50)
{
    cout<<"Invalid input. Enter a positive Position number less than 51\n"<<
    "where String 2 is to be inserted: ";
    cin>>position;
}

insertString(str1,str2,position);

cout<<"Modified string 1: "<<str1<<endl;

system("pause");
return 0;

}

/******************************************************************************
Definition of function insertString:

This function takes two C-string in form of character arrays and one integer value
as parameters

It inserts String 2 in String 1 on the required position.

*******************************************************************************/

void insertString(char str1[ ],char str2[ ],int position)
{
char temp[SIZE];
int i,j,countStr2;

for(j=0;j<SIZE&&str2[j]!=0;j++)
    countStr2=j;
    
for(i=position,j=0;i<SIZE,j<=countStr2; i++,j++)
{
    temp[i]=str1[i];
    str1[i]=str2[j];
    
}

}

This logic overwrites some characters of string 1. What should I do?

Any help will be appreciated.

</details>


# 答案1
**得分**: 2

```cpp
#include <cstring>
#include <iostream>
/*The following function supposes that str1 and str2 are cString (i.e) ended by `

This logic overwrites some characters of string 1. What should I do?
Any help will be appreciated.
</details>
# 答案1
**得分**: 2
```cpp
#include <cstring>
#include <iostream>
/*The following function supposes that str1 and str2 are cString (i.e) ended by `\0` and inserts str2 in str1 at the specified position in a newStr, then returns the new string as a pointer*/
char* insertString(const char str1[], const char str2[], const int& position)
{
int shiftedPos = position - 1;
int str2Size = strlen(str2);
int str1Size = strlen(str1);
int newSize = str2Size + str1Size + 1;
char* newStr = new char[newSize];
for (int i = 0; i < shiftedPos; i++) newStr[i] = str1[i];
for (int i = 0; i < str2Size; i++) newStr[shiftedPos + i] = str2[i];
for (int i = 0; i < newSize; i++) newStr[shiftedPos + str2Size + i] = str1[shiftedPos + i];
newStr[newSize] = '\0';
return newStr;
}
int main(){
auto str1 = "I have apple";
auto str2 = "an ";
std::cout << insertString(str1, str2, 8);
return 0;
}
` and inserts str2 in str1 at the specified position in a newStr, then returns the new string as a pointer*/

char* insertString(const char str1[], const char str2[], const int& position)
{
    int shiftedPos = position - 1;
    int str2Size = strlen(str2);
    int str1Size = strlen(str1);
    int newSize = str2Size + str1Size + 1;

    char* newStr = new char[newSize];
    for (int i = 0; i < shiftedPos; i++) newStr[i] = str1[i];

    for (int i = 0; i < str2Size; i++) newStr[shiftedPos + i] = str2[i];
    for (int i = 0; i < newSize; i++) newStr[shiftedPos + str2Size + i] = str1[shiftedPos + i];

    newStr[newSize] = '

This logic overwrites some characters of string 1. What should I do?
Any help will be appreciated.
</details>
# 答案1
**得分**: 2
```cpp
#include <cstring>
#include <iostream>
/*The following function supposes that str1 and str2 are cString (i.e) ended by `\0` and inserts str2 in str1 at the specified position in a newStr, then returns the new string as a pointer*/
char* insertString(const char str1[], const char str2[], const int& position)
{
int shiftedPos = position - 1;
int str2Size = strlen(str2);
int str1Size = strlen(str1);
int newSize = str2Size + str1Size + 1;
char* newStr = new char[newSize];
for (int i = 0; i < shiftedPos; i++) newStr[i] = str1[i];
for (int i = 0; i < str2Size; i++) newStr[shiftedPos + i] = str2[i];
for (int i = 0; i < newSize; i++) newStr[shiftedPos + str2Size + i] = str1[shiftedPos + i];
newStr[newSize] = '\0';
return newStr;
}
int main(){
auto str1 = "I have apple";
auto str2 = "an ";
std::cout << insertString(str1, str2, 8);
return 0;
}
';

    return newStr;
}
int main(){
    auto str1 = "I have apple";
    auto str2 = "an ";
    std::cout << insertString(str1, str2, 8);
    return 0;
}

#include<cstring>
#include <iostream>
/*The following function supposes that str1 and str2 are cString (i.e)
ended by `
#include<cstring>
#include <iostream>
/*The following function supposes that str1 and str2 are cString (i.e)
ended by `\0` and inserts str2 in str1 at the specified position in a
newStr, then returns the new string as apointer*/
char* insertString(const char str1[ ],const char str2[ ],const int& position)
{
int shiftedPos=position-1;
int str2Size=strlen(str2);
int str1Size=strlen(str1);
int newSize=str2Size+str1Size+1;
char* newStr=new char[newSize];
for(int i=0; i<shiftedPos; i++) newStr[i]=str1[i];
for(int i=0; i<str2Size; i++) newStr[shiftedPos+i]=str2[i];
for(int i=0; i<newSize; i++) newStr[shiftedPos+str2Size+i]=str1[shiftedPos+i];
newStr[newSize]='\0';
return newStr;
}
int main(){
auto str1 = "I have apple";
auto str2 = "an ";
std::cout<<insertString(str1,str2, 8);
return 0;
}
` and inserts str2 in str1 at the specified position in a
newStr, then returns the new string as apointer*/

char* insertString(const char str1[ ],const char str2[ ],const int& position)
{
    int shiftedPos=position-1;
    int str2Size=strlen(str2);
    int str1Size=strlen(str1);
    int newSize=str2Size+str1Size+1;

    char* newStr=new char[newSize];
    for(int i=0; i<shiftedPos; i++) newStr[i]=str1[i];

    for(int i=0; i<str2Size; i++) newStr[shiftedPos+i]=str2[i];
    for(int i=0; i<newSize; i++) newStr[shiftedPos+str2Size+i]=str1[shiftedPos+i];

    newStr[newSize]='
#include<cstring>
#include <iostream>
/*The following function supposes that str1 and str2 are cString (i.e)
ended by `\0` and inserts str2 in str1 at the specified position in a
newStr, then returns the new string as apointer*/
char* insertString(const char str1[ ],const char str2[ ],const int& position)
{
int shiftedPos=position-1;
int str2Size=strlen(str2);
int str1Size=strlen(str1);
int newSize=str2Size+str1Size+1;
char* newStr=new char[newSize];
for(int i=0; i<shiftedPos; i++) newStr[i]=str1[i];
for(int i=0; i<str2Size; i++) newStr[shiftedPos+i]=str2[i];
for(int i=0; i<newSize; i++) newStr[shiftedPos+str2Size+i]=str1[shiftedPos+i];
newStr[newSize]='\0';
return newStr;
}
int main(){
auto str1 = "I have apple";
auto str2 = "an ";
std::cout<<insertString(str1,str2, 8);
return 0;
}
';

    return newStr;
}
int main(){
    auto str1 = "I have apple";
    auto str2 = "an ";
    std::cout<<insertString(str1,str2, 8);
    return 0;
}

#include<iostream>
#include<cstring>
/*The following function supposes that str1 and str2 are cString (i.e)
ended by `
#include<iostream>
#include<cstring>
/*The following function supposes that str1 and str2 are cString (i.e)
ended by `\0` and that the memory allocated by str1 >= the len(str1)+len(str2)+1.
It inserts str2 in str1 at the specified position in str1*/
void insertString(char str1[ ], char str2[ ], int position)
{
int str1Size=strlen(str1);
int str2Size=strlen(str2);
int newSize=str2Size+str1Size+1;
int cppPosition=position-1;
for(int i=str1Size; i>=cppPosition; i--) str1[i+str2Size]=str1[i];
for(int i=0; i<str2Size; i++) str1[cppPosition+i]=str2[i];
str1[newSize]='\0';
}
int main(){
char str1[50]= "I have apple";
char str2[50] = "an ";
insertString(str1,str2, 8);
std::cout<<str1;
return 0;
}
` and that the memory allocated by str1 >= the len(str1)+len(str2)+1.
It inserts str2 in str1 at the specified position in str1*/

void insertString(char str1[ ], char str2[ ], int position)
{
    int str1Size=strlen(str1);
    int str2Size=strlen(str2);
    int newSize=str2Size+str1Size+1;
    int cppPosition=position-1;

    for(int i=str1Size; i>=cppPosition; i--) str1[i+str2Size]=str1[i];
    for(int i=0; i<str2Size; i++) str1[cppPosition+i]=str2[i];
    str1[newSize]='
#include<iostream>
#include<cstring>
/*The following function supposes that str1 and str2 are cString (i.e)
ended by `\0` and that the memory allocated by str1 >= the len(str1)+len(str2)+1.
It inserts str2 in str1 at the specified position in str1*/
void insertString(char str1[ ], char str2[ ], int position)
{
int str1Size=strlen(str1);
int str2Size=strlen(str2);
int newSize=str2Size+str1Size+1;
int cppPosition=position-1;
for(int i=str1Size; i>=cppPosition; i--) str1[i+str2Size]=str1[i];
for(int i=0; i<str2Size; i++) str1[cppPosition+i]=str2[i];
str1[newSize]='\0';
}
int main(){
char str1[50]= "I have apple";
char str2[50] = "an ";
insertString(str1,str2, 8);
std::cout<<str1;
return 0;
}
';
}
int main(){
    char str1[50]= "I have apple";
    char str2[50] = "an ";
    insertString(str1,str2, 8);
    std::cout<<str1;
    return 0;
}

答案2

得分: 1

如果你必须实现void insertString(char str1[], char str2[], int position)函数，你没有太多选择。

其中一个可能的解决方案是将第一个字符串中的字符向右移动，以便插入第二个字符串。

这种方法可能如下所示：

void insertString(char str1[], char str2[], int position) {
    const int len1 = strlen(str1);
    const int len2 = strlen(str2);
    
    // 首先，将给定位置之后的所有字符向右移动`len2`个位置：
    for (int i = 0; i < len1 - position; ++i) {
        str1[len1 - i - 1 + len2] = str1[len1 - i - 1];
    }
    // 然后在给定位置插入第二个字符串：
    for (int i = 0; i < len2; ++i) {
        str1[position + i] = str2[i];
    }
    // 确保创建一个新的终止符，因为
    // 第一个循环中的终止符已被覆盖
    str1[len1 + len2 + 1] = 0;
}

注意，这是潜在的不安全操作！如果str1数组中没有足够的空间来存储另外strlen(str2)个字符，这将导致缓冲区溢出。

更安全的选项是在堆上为新的连接字符串分配一个新的缓冲区，但是出于作业的考虑，这应该足够了。

由于你正在使用C ++，在任何生产代码中，你应该完全避免这种方法，可以使用std::string等替代字符数组。但我已经在评论中看到你目前还不能使用它。

void insertString(char str1[], char str2[], int position) {
    const int len1 = strlen(str1);
    const int len2 = strlen(str2);
    
    // First, shift all the characters from the given position to the right by `len2` positions:
    for (int i = 0; i < len1 - position; ++i) {
        str1[len1 - i - 1 + len2] = str1[len1 - i - 1];
    }
    // Then insert the second string in the given position:
    for (int i = 0; i < len2; ++i) {
        str1[position + i] = str2[i];
    }
    // Make sure to create a new terminator since the
    // previous one got overwritten by the the first loop
    str1[len1 + len2 + 1] = 0;
}

答案3

得分: 1

假设您可以使用<string>，那么我会使用std::string::substr：

  #include <string>

  std::string originalString = "I have apple"; // 原始字符串
  std::string insert = " an "; // 在新单词插入前面添加的空格
  int position = 6; // 新单词将插入的索引位置
  
  int remainingStringSize = originalString.length() - position - 1; // 计算从插入位置开始剩余的字符数
  
  std::string combinedString = originalString.substr(0, 6) + insert + originalString.substr(position + 1, remainingStringSize); // 结果组合字符串

注意事项，您显然需要检查以下内容：

• 插入位置的索引是否在原始字符串的长度范围内
• 剩余字符数是否大于0

  #include <string>

  std::string originalString = "I have apple"; // original string
  std::string insert = " an "; // added space beforehand for the new word to be inserted
  int position = 6; // index where the new word would be inserted
  
  int remainingStringSize = originalString.length() - position - 1; // count how many characters remain from the position you're inserting
  
  std::string combinedString = originalString.substr(0, 6) + insert + originalString.substr(position +1, remainingStringSize); // resulting combined string