分段错误(核心转储)C++错误

Question

我使用以下代码获得"Segmentation fault(core dumped)"错误:

#include <iostream>
#include <cstring>

template <class T>
T maxn(T* elements, int n);

template <> const char* maxn <const char*>(const char* elements[], int num);

int main(){
    using namespace std;

    //Using template
    int num[6] = {2, 3, 4, 5, 6, 22};
    double num2[4] = {16.6, 10.5, 2.3, 1.1};

    int larg = maxn(num, 6);
    double larg2 = maxn(num2, 4);
    cout << larg << endl << larg2 << endl;

    //Using specialization
    const char* pps[5] = {"Hello", "There", "I", "am", "me"};
    const char* largest = maxn(pps, 5);
    cout << largest << endl; 
    return 0;


}    

//return largest element in an array of T of n elements
template <class T>
T maxn(T* elements, int n){
    T largest = 0;
    for (int i=0; i<n; i++)
        largest = elements[i] > largest ? elements[i] : largest;
    return largest;
}    

//Returns address that points to the largest string
template <> const char* maxn <const char*>(const char* elements[], int num){
    int longest = 0;
    int i =0;
    for (i=0; i<num; i++)
        if (strlen(elements[i]) > strlen(elements[longest]))
            longest = i;
    return elements[i];
} 

我得到了"警告:从字符串常量弃用转换为'char*'错误但后来我将一些char*数组和函数参数更改为const char*并且我摆脱了它.现在代码编译,我得到以下输出:

22

16.6

分段故障(核心转储)

前两行是正确的,但我无法理解第三行会发生什么.请帮忙,谢谢.

Answer 1

您返回的元素超出范围:

return elements[i];

应该:

return elements[longest];

我可以建议i在for循环中声明:

for (int i=0; i<num; i++)
//   ^^^^^^^

然后行将return elements[i];抛出编译时错误.

当然,你应该优先考虑内置函数和容器:)