从函数获取二维数组，返回一个int C++

Question

我有一个模拟骰子游戏的任务。作为该程序的一部分，用户输入掷骰子的数量以及掷骰子的次数。如果用户滚动4个骰子，程序应该将这4个值相加，将结果存储在一个数组中，然后按照用户定义的次数重新执行程序。主代码和函数原型是由我们的导师定义的，不能修改。我们必须写这个函数。

在主的步骤3中，有两个用于循环。内循环调用有问题的函数。二维数组rollSums [] []被分配给函数的结果。这个数组将被用在另一个函数中。我无法弄清楚如何从函数中正确地填充二维数组。代码和我在函数尝试低于：

#include <iostream> 
#include <iomanip> 
#include <cstdlib> // needed for functions srand() and rand() 
#include <ctime> // needed for function time() 
#include <cmath> // needed for sqrt() 

using namespace std; 

const int MAXNUMTOROLL=10; 
const int MAXROLLS=100; 


int rollDice(int diceVals[], int numToRoll); 

int main() 
{ 
    int sum; 
    int rollSums[MAXNUMTOROLL][MAXROLLS]; 
    int diceVals[MAXROLLS]; 
    double mean[MAXNUMTOROLL], std[MAXNUMTOROLL]; 
    int numToRoll, numRolls; 

    srand(time(NULL)); 

    // STEP 1: Ask user to input the maximum number of dice to use: 

    cout << "Please enter the maximum number of dice to use:" << endl; 
    do 
    { 
     cin >> numToRoll; 
    } while (numToRoll < 0 || numToRoll > MAXNUMTOROLL); 

    cout << "Please enter the number of rolls:" << endl; 

    // STEP 2: Ask user to input the number of rolls to carry out: 
    do 
    { 
     cin >> numRolls; 
    } while (numRolls < 0 || numRolls > MAXROLLS); 

    // STEP 3: For k=1 to numToRoll, simulated numRolls rolls of the dice 
    // and store the sum of the numbers rolled in the array rollSums[][] 

    for (int k=1;k<=numToRoll;k++) 
    { 
     for (int i=0;i<numRolls;i++) 
    { 
     rollSums[k-1][i] = rollDice(diceVals, k); 
    } 
    } 

    return 0; 
} 

int rollDice(int diceVals[], int numToRoll) //function simulating throwing of dice 
{ 
int sum=0; 
int i=0; 

for(i=0;i<numToRoll;i++) 
{ 
    diceVals[i]=1+rand()%6; 
    sum=sum+diceVals[i]; 
} 
return sum; 
} 

Answer 1

adohertyd，看到代码样本中我的意见：

#include <iostream> 
#include <iomanip> 
#include <cstdlib> // needed for functions srand() and rand() 
#include <ctime> // needed for function time() 
#include <cmath> // needed for sqrt() 

using namespace std; 

const int MAXNUMTOROLL=10; 
const int MAXROLLS=100; 
const bool show_debug = true; 

int rollDice(int diceVals[], int numToRoll); 

int main() 
{ 
    int roll_Sums[MAXNUMTOROLL]; 
    int diceVals[MAXROLLS]; 
    //double mean[MAXNUMTOROLL], std[MAXNUMTOROLL]; 
    int numDice, numThrows; 

    //Initialize random number generator with the current time 
    srand(time(NULL)); 

    // STEP 1: Ask user to input the maximum number of dice to use: 
    cout << "Please enter the maximum number of dice to use:" << endl; 

    // STEP 2: Validate number of dice input 
    do 
    { 
     cin >> numDice; 
    } while (numDice < 0 || numDice > MAXNUMTOROLL); 

    //STEP 3: Ask user to input the number of times to throw each dice 
    cout << "Please enter the number of rolls:" << endl; 

    // STEP 4: Validate number of throws input 
    do 
    { 
     cin >> numThrows; 
    } while (numThrows < 0 || numThrows > MAXROLLS); 

    cout << "\n\nThrowing Dice Now...\n\n"; 

    // STEP 5: Roll the dice 
    //The loop deals with each dice 
    for (int diceCount = 0; diceCount < numDice; diceCount++) 
    { 
     //The function call deals with all the throws per dice 
     //Note: roll_Sums array didn't need to be two dimensional, 
     //  also, rollDice gets passed diceVals[] by value and the number of throws to execute 
     roll_Sums[diceCount] = rollDice(diceVals, numThrows); 

     //Debug output 
     if(show_debug) 
     { 
      //Since roll_Sums is zero based, add one to the visible index so the user doesn't get confused :P 
      cout << "Roll Sum for dice #" << diceCount + 1 << ": " << roll_Sums[diceCount] << endl << endl; 
     }  
    } 

    return 0; 
} 

//rollDice() returns the sum of all the dice rolls it performed 
int rollDice(int diceVals[], int numToRoll) 
{ 
    int sum=0; 

    for(int i=0;i<numToRoll;i++) 
    { 
     //Get your random dice rolls 
     diceVals[i]=1+rand()%6; 

     //Debug output 
     if(show_debug) 
     { 
      cout << "Dice Roll # " << i+1 << ": " << diceVals[i] << endl; 
     } 

     //Accumulate your value, e.g. "sum" 
     sum += diceVals[i]; 
    } 

    return sum; 
}