C ++中的二進制搜索排序和索引

Question

問題：給定一個數組（ArrayInts），計算所有偶數和，奇數整數的和，並使用Binary Search在數組中搜索所有奇數整數和的目標值。 如果在數組內找到目標值，則顯示找到目標值的數組索引，否則顯示未找到目標。

我沒有得到正確的答案。 我不相信我要讀取的數組正在讀取。 編譯時，我得到的數組是{6487456}，偶數之和是678，賠率是549，未找到二進制搜索目標。 現在是我的代碼：

#include <stdio.h> 
#include <stdlib.h>
#include <math.h>


double ArrayInts[]={54,152,99,-8,3,19,-11,260,27,-4,10,12,15,58,480,60};
int Bin_Search(double ArrayInts[],int low, int high, double target);

int main(void)
{
int i,j,n=16,sum_even,sum_odd, index,len;
double ArrayInts[16]={54,152,99,-8,3,19,-11,260,27,-4,10,12,15,58,480,60}, target;

//Implemeting Bubble sort
for(i=0;i<n-1;i++)
    for(j=0;j<n-1;j++)
    {
        if (ArrayInts[j]>ArrayInts[j+1])
        {
            len=ArrayInts[j];
            ArrayInts[j]=ArrayInts[j+1];
            ArrayInts[j+1]=len;
        }
    }

//Function call to add even and odd numbers from array
for(i=0;i<16;i++)
{
    if(i%2==0)
    sum_even+=ArrayInts[i];

    else
    sum_odd+=ArrayInts[i];
}

printf("The array is {%d}\n",ArrayInts);
printf("The sum of all even numbers in the array is: %d\n",sum_even);
printf("The sum of all odd numbers in the array is: %d\n",sum_odd);

//Function call to search for target value
index = Bin_Search(ArrayInts,0,15,target); 

if(index != -1)
printf("Target found at index %d\n", index);
else
printf("Target was not found\n");

system("pause");
return (0);
}

int Bin_Search(double ArrayInts[],int low, int high, double target)
{
int mid;

if (low>high)
    return -1;

mid=(low+high)/2;
if(ArrayInts[mid]==target)
    return(mid);

else if (ArrayInts[mid]<target)
    return Bin_Search(ArrayInts, mid+1, high, target);
else
    return Bin_Search(ArrayInts, low, mid-1, target);     
}

Answer 1

sum_even未初始化。

sum_odd未初始化。

target未初始化。

這些變量均未初始化。 因此，這導致未定義的行為。

假設這是c++ ，請使用std::sort對數組進行排序，而不是對自己的排序進行編碼。 如果這確實是C ，請改用qsort（3） 。

Answer 2

使用range / V3 ，它將是：

std::vector<int> v = {54,152,99,-8,3,19,-11,260,27,-4,10,12,15,58,480,60, 480-163};
auto is_even = [](int i) {return i % 2 == 0;};
auto is_odd = [](int i) {return i % 2 == 1;};

const auto even_sum = ranges::v3::accumulate(v | ranges::v3::view::filter(is_even), 0);
const auto odd_sum = ranges::v3::accumulate(v | ranges::v3::view::filter(is_odd), 0);
ranges::v3::sort(v);
const auto target = 27;
auto found = ranges::v3::binary_search(v, target);

std::cout << "The sum of all even numbers in the array is:" << even_sum << std::endl;
std::cout << "The sum of all odd numbers in the array is:" << odd_sum << std::endl;
std::cout << target << (found ? " Found" : " Not found") << std::endl;

演示版