輸入時，它讀取不匹配/通過第二次（C++）

Question

所以我是相當新的編碼和C++。所以......對不起，如果這是值得一些你非常明顯：

我有一個很難得到這個代碼讀取存儲在txt文件第二次輸入。它第一次運作。

void readcode(ifstream& infile, int list[], int& length, bool& lenCodeOk) 
{ 
    int count; 
    lenCodeOk = true; 

    infile >> length; //get the length of the secret code 
    cout << "Length1 is "<<length<<endl; 


    if (length > MAX_CODE_SIZE) 
    { 
      lenCodeOk = false; 
      return; 
    } 
      //Get the secret code. 

    for (count = 0; count < length; count++) 
    { 
      infile >> list[count]; 
    } 

    cout<<" Code recorded is: "; 
    for (count = 0; count < length; count++) 
    { 
      cout<<list[count]<<" "<<endl; 
    } 
} 

所以在我的txt文件的第一個整數整數序列的長度。這個函數完成它應該做的所有事情。正確讀取長度也會將所有內容存儲在數組中。

但是當我在調用readcode函數後調用下面的compareCode函數時，它會出現一個完全隨機的/不同的長度（我每次調用時都會改變一次）和數組元素。

void compareCode(ifstream& infile, ofstream& outfile, const int list[], int length) 
{ 

    int length2; 
    int digit; 
    bool codeOk; 
    int count; 

    codeOk = true; 

    infile >> length2; 

    cout<<"Length2 is "<<length<<endl; 


    if(length != length) 
    { 
      cout<< "The original code and its copy are not of the same length"<<endl; 
      return; 
    } 


    outfile << "Code Digit Code Digit Copy"<<endl; 
    for (count= 0; count<length; count++) 
    { 
      infile >> digit; 
      outfile<<setw(5)<<list[count]<<setw(17)<<digit; 

      if (digit != list[count]) 
      { 
        outfile << " Code digits are not the same"<<endl; 
        codeOk = false; 
      } 
      else 
      { 
        outfile<<endl; 
    } 

      if (codeOk) 
      { 
        outfile<<"Message transmitted OK."<<endl; 
      } 
      else 
      { 
        outfile<<"Error in transmission. "<<"Retransmit!!"<<endl; 

       } 

    } 
} 

好像我缺少的一個重要信息有關傳遞fstream的變量，如果有人指着我朝着正確的方向我會很感激。

int main() 
{ 

    int codeArray[MAX_CODE_SIZE];//Array to store the secret code 
    int codeLength;// Variable to store the length of the code 
    int codeLength2; 
    bool lengthCodeOk;//Variable to indicate if the legth of the secret code is less than or equal to 250 

    ifstream incode;// Declare ifstream variable 
    ofstream outcode;//Declare ofstream variable 

    char inputFile[51];//Variable to store the name of the input file 
    char outputFile[51]; //Variable to store the name of the output file 

    cout<<"Enter the input file name: "<<endl; 
    cin>> inputFile;//makesure it is one word because ci.>>skips white space 
    cout<<endl; 

    incode.open(inputFile); 
    if(!incode) 
    { 
      cout<< "Cannot open the input file."<<endl; 
      return 1; 
    } 

    cout<< "Enter the output file name: " ; 
    cin>> outputFile;//Same deal, one word so cin>> can read 
    cout<<endl; 


    outcode.open(outputFile); 

    readcode(incode,codeArray,codeLength,lengthCodeOk); 
    if (lengthCodeOk) 
    { 
      compareCode(incode,outcode,codeArray,codeLength); 
    } 
    else 
    { 
      cout<<"Length of the secret code must be <= "<<MAX_CODE_SIZE<<endl; 
    } 

    incode.close(); 
    outcode.close(); 

    return 0; 
} 

Answer 1

這應該是這樣的：

istream& readcode(istream& infile, std::vector<int>& list) 
{ 
    int length; 
    if (infile >> length) { 
     list.reserve(length); 
     for (int count = 0; count < length; count++) 
     { 
      int x; 
      if (infile >> x) 
      { 
       list.push_back(x); 
      } else { 
       break; 
      } 
     } 
    } 
    return infile; 
} 

ifstream file("somefile.txt"); 
if (file.good()) 
{ 
    std::vector<int> a, b; 
    if (readcode(file, a).good()) 
    { 
     file.seekg(0); 
     if (readcode(file, b).good()) 
     { 
      cout << (a!=b? "code reading are different" : "code reading are same") << endl; 
     } 
     else 
     { 
      cerr << "failed read again code" << endl; 
     } 
    } 
    else 
    { 
     cerr << "failed read code" << endl; 
    } 
}