C++：變量'f'未初始化

Question

我在C++上創建基於文本的風險遊戲。一直試圖實現骰子/戰鬥功能，但它一直給我錯誤「f未經初始化使用！」這很奇怪，因爲我早些時候初始化了它。這裏是我的代碼

void battle(int attack, int defend) 
{ 
    int a, b, c, d, e, f; 

    if (attack >= 3) 
    { 
     a = rollDice(); 
     b = rollDice(); 
     c = rollDice(); 
    } 

    else if (attack == 2) 
    { 
     a = rollDice(); 
     b = rollDice(); 
     c = 0; 
    } 

    else if (attack == 1) 
    { 
     a = rollDice(); 
     b = 0; 
     c = 0; 
    } 

    else if (defend >= 2) 
    { 
     d = rollDice(); 
     e = rollDice(); 
     f = 0; 
    } 

    else if (defend == 1) 
    { 
     d = rollDice(); 
     e = 0; 
     f = 0; 
    } 

    sortValues(a, b, c); 
    sortValues(d, e, f); 

    cout << endl << "The attacking country rolled the following dices: " << a 
      << " " << b << " " << c << "."; 
    cout << endl << "The defending country rolled the following dices: " << d 
      << " " << e << " " << f << "."; 

    if (a == d) 
    { 
     attack = attack - 1; 
    } 

    else if (a != d) 
    { 
     if (a < d) 
     { 
      attack = attack - 1; 
     } 

     else if (a > d) 
     { 
      defend = defend - 1; 
     } 
    } 

    else if (b == e) 
    { 
     attack = attack - 1; 
    } 

    else if (b != e) 
    { 
     if (b < e) 
     { 
      attack = attack - 1; 
     } 

     else if (b > e) 
     { 
      defend = defend - 1; 
     } 
    } 

// since the int f is never used, this function is critical to implement. so that we can avoid compile time error 
    _unused(f); 
} 

int main() 
{ 

    int attack; 
    int defend; 
    int choice; 

// this asks for the user choice of what he would like to do. 

    cout << "How large is the attacking army?" << endl; 
    cin >> attack; 
    cout << "How large is the defending army?" << endl; 
    cin >> defend; 

    while (attack >= 1 && defend >= 1) 
    { 
     cout 
       << "Based on the numbers you entered, you have a couple of choices: " 
       << endl << endl; 

     cout << "1) Battle once" << endl; 
     cout << "2) Battle until the end" << endl; 
     cout << "3) Withdraw from the battle" << endl; 

     cout << "Please enter your game choice (just enter the number): " 
       << endl; 
     cin >> choice; 

     if (choice == 1) 
     { 
      battle(attack, defend); 
     } 

     if (choice == 2) 
     { 
      do 
      { 
       battle(attack, defend); 
      } while (attack != 0 && defend != 0); 

      cout << "Battle ended. The attacking forces are: " << attack 
        << " , while the defending forces are: " << defend << endl; 
     } 

     if (choice == 3) 
     { 
      break; 
     } 
    } 

    if (attack < 1) 
    { 
     cout 
       << "The attacking forces have lost. Defending forces keep their territory" 
       << endl; 
    } 

    else if (defend < 1) 
    { 
     cout << "The attacking forces have won over the territory." << endl; 
    } 

    system("pause"); 
    return 0; 
} 

這不是所有的代碼，但它是包含和使用f的關鍵部分。

Answer 1

在battle函數中，您打電話sortValues(d,e,f)，但在前3個if-cases f沒有得到一個值（因此未初始化）。

其實你應該得到類似的錯誤（這是真的錯誤或警告？）爲d和在某些情況下，你不給價值a，b和c。