在LC容易问题中使用向量会不断导致某种段错误Seg Fault Error 代码：

如何解决在LC容易问题中使用向量会不断导致某种段错误Seg Fault Error 代码：

Leetcode问题：

Given the array nums consisting of 2n elements in the form [x1,x2,...,xn,y1,y2,yn].

Return the array in the form [x1,yn].

 

Example 1:

Input: nums = [2,5,1,3,4,7],n = 3
Output: [2,7] 
Explanation: Since x1=2,x2=5,x3=1,y1=3,y2=4,y3=7 then the answer is [2,7].

这是我的代码：

class Solution {
public:
    vector<int> shuffle(vector<int>& nums,int n) {
        /*
        1    2  3  4  5  6
        [x1,x3,y3]
        [x1,y3]
        
        when combined,x will always be odd,y will always be even
        
        */
        
        //declare vectors
        vector<int> x (n,0);
        vector<int> y (n,0);
        vector<int> result(2*n,0);
        
        //split nums param array
        for(int i = 0; i < n; i++){
            x[i] = nums[i];
        }
        
        for(int i = n; i < sizeof(nums); i++){
            y[i] = nums[i];
        }
        
        int xCount = 0;
        int yCount = 0;
        
        //combine
        for(int i = 0; i < result.size(); i++){
            if(i % 2 != 0){ //if odd
                result[i] = x[xCount];
                xCount++;
            }
            else{
                result[i] = y[yCount];
                yCount++;
            }
        }
        
        return result;      
    }
};

我不断收到此编译错误：

=================================================================
==30==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6020000000dc at pc 0x000000376b62 bp 0x7ffeb6f4acb0 sp 0x7ffeb6f4aca8
WRITE of size 4 at 0x6020000000dc thread T0
    #3 0x7fb40ba770b2  (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
0x6020000000dc is located 0 bytes to the right of 12-byte region [0x6020000000d0,0x6020000000dc)
allocated by thread T0 here:
    #10 0x7fb40ba770b2  (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
Shadow bytes around the buggy address:
  0x0c047fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff8000: fa fa fd fa fa fa fd fa fa fa fd fa fa fa fd fa
=>0x0c047fff8010: fa fa fd fd fa fa 00 04 fa fa 00[04]fa fa fa fa
  0x0c047fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
  Shadow gap:              cc
==30==ABORTING

到底发生了什么？

我认为这可能与滥用向量有关……或者访问了一个不存在的索引……但是我正在检查我的代码，并且我相信它在范围之内（尽管解决方案可能不正确） ）。只是为这个编译错误而烦恼...

解决方法

那是运行时错误，而不是编译器错误。

看代码，我会说sizeof(nums)应该是nums.size()。

,

• 您可能在此行（y[i] = nums[i];）中遇到错误。

• 您也可以将sizeof更改为std::size：

    for(int i = n; i < sizeof(nums); i++){
        y[i] = nums[i];
    }
  

收件人：

    int index = 0;
    for(int i = n; i < std::size(nums); i++){
        y[index] = nums[i];
        ++index;
    }

我们可以使用更少的语句更轻松，更有效地解决问题：

        std::vector<int> res;

        for (int index = 0; index < n; index++) {
            res.emplace_back(nums[index]);
            res.emplace_back(nums[n + index]);
        }


        return res;

代码：

// The following block might slightly improve the execution time;
// Can be removed;
static const auto __optimize__ = []() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    std::cout.tie(nullptr);
    return 0;
}();

// Most of headers are already included;
// Can be removed;
#include <cstdint>
#include <vector>

static const struct Solution {
    using ValueType = std::uint_fast16_t;
    static const std::vector<int> shuffle(
        std::vector<int>& nums,const int n
    ) noexcept {
        std::vector<int> res;

        for (ValueType index = 0; index < n; index++) {
            res.emplace_back(nums[index]);
            res.emplace_back(nums[n + index]);
        }


        return res;
    }
};


// // The following block might slightly improve the execution time;
// // Can be removed;
// static const auto __optimize__ = []() {
//     std::ios::sync_with_stdio(false);
//     std::cin.tie(nullptr);
//     std::cout.tie(nullptr);
//     return 0;
// }();

// // Most of headers are already included;
// // Can be removed;
// #include <cstdint>
// #include <vector>

// static const struct Solution {
//     using ValueType = std::uint_fast16_t;
//     static constexpr std::vector<int>& shuffle(
//         std::vector<int>& nums,//         int n
//     ) noexcept {
//         for (ValueType slow = 0,fast = 0; fast < nums.size() - 1; ++slow,fast += 2) {
//             nums[fast] |= ValueType(nums[slow]) << 16;
//             nums[fast + 1] |= ValueType(nums[slow + n]) << 16;
//         }

//         for (auto& num : nums) {
//             num >>= 16;
//         }

//         return nums;
//     }
// };