如何在旁边添加两个ints以制作一个int

Question

我有以下程序，它采用数组形式，例如：[12,34,55,6] 我正在使用 for 和 while 循环逐个字符读取，如果读取了一个数字，它将存储在向量 SumVec 中，即我面临的问题是向量一次只存储一个数字有什么办法可以解决这个问题。

#include <iostream>
#include <vector>

using namespace std;

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {

    }

    vector <int> SumVec;
    string Nums;
    int ReadNums(__int32* Array);
    __int32 ArraySize;
   


};
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file

int Solution::ReadNums(__int32* Array){
    ArraySize = 0;
    Array = new int[ArraySize];

    for (int i = 0; i < Nums.size(); ++i) {

      if (Nums[i] == '[' || Nums[i] == ']'|| Nums[i] == ',' || Nums[i] == ' ');  //do nothing  
      else {
          int j = i;

          while (1) {
              
              ++j;

              if (Nums[j] != '[' && Nums[j] != ']' && Nums[j] != ',') {
                  SumVec.push_back(Nums[j]);
              }
              else 
                    SumVec.push_back(Nums[i]);

          }
      }
    }

 return ArraySize;
}

int main()
{
  

    std::cout << "Welcome to the Two Sum!\n";
    Solution Soln;
    cout << "nums = ";  //[12,34,55,6]
    cin>>Soln.Nums ;
    __int32* ArrayRequst = new __int32[Soln.ArraySize];
   Soln.ReadNums(ArrayRequst);


   for (auto i = Soln.SumVec.begin();i!= Soln.SumVec.end(); ++i){
        cout << *i << endl;
    }

}

当前输入：[12,34,55,6]

当前输出：

1 
2
3
4
5
5
6

Answer 1

你可以这样做：

• 使用字符串流解析您的输入字符串，然后
• 将您的数字直接读入ints 的向量中。

[Demo]

#include <iostream>  // cout
#include <sstream>  // stringstream
#include <string>
#include <vector>

int main()
{
    const std::string line{"[12,34,55,6]"};
    std::stringstream ss{line};
    
    char c{};
    ss >> c;  // read '['
    
    std::vector<int> nums{};
    int num{};
    while (ss >> num >> c)  // read <number>',' or <number>']'
    {
        nums.push_back(num);
    }
    for (auto& num : nums)
    {
        std::cout << num << "\n";
    }
}

// Outputs:
//   12
//   34
//   55
//   6

Answer 2

我在整个代码中进行了一些更改并编写了 cmets

#include <iostream>
#include <vector>
#include <cctype>
#include <string>

using namespace std; 
// first of all, using namespace std is generally not a great idea. 
// Because if it's in a header file, you can force it upon others(but it's not a problem here)

class Solution {
public:
    vector<int> twoSum(vector<int>& nums, int target) {
    }

    vector <int> SumVec;
    string Nums;
    // changed all the __int32 to normal int's, it just makes the code incompatible in my opinion
    int ReadNums(); 
    //int ArraySize; this is not necessary since we can just do SumVec.size() 
   


};
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file

int Solution::ReadNums(){
    for (int i = 0; i < Nums.size(); ++i) {
        if (Nums[i] == '[') continue;
        // if (Nums[i] == ']'|| Nums[i] == ',' || Nums[i] == ' ');  
        //do nothing, is a bit weird, just test for the other case (isdigit), or negate the result  
        if (std::isdigit(Nums[i])) {
            int j = i;
            string buffer;
            while (true) {
                if (Nums[j] == '[' || Nums[j] == ']' || Nums[j] == ','){
                    SumVec.push_back(std::stoi(buffer));
                    break;
                }
                // as long as we are reading digits, append them to a buffer
                else if (std::isdigit(Nums[j])){
                    buffer += Nums[j];
                    ++i; 
                    // increment the i value, we dont want to loop twice over the same digit
                }
                    
                ++j;
          }
      }
    }

 return SumVec.size(); // as said not necassary
}

int main()
{
  

    std::cout << "Welcome to the Two Sum!\n";
    Solution Soln;
    cout << "nums = ";  //[12,34,55,6]
    cin>>Soln.Nums ;
    Soln.ReadNums();


   for (auto i: Soln.SumVec){
        cout << i << endl;
    }

}

最后我不明白你为什么使用 __int32* ArrayRequst = new __int32[Soln.ArraySize]; 所以我忽略了它。