Question

这是我第一次制作结构数组。基本上我试图做一种直方图。这是分析我提供的字符串并打印出哪个字母出现次数最多。另外我想说我的程序确实有效！我得到了所有正确的结果。但是当程序完成计算并显示它们时，它会崩溃。我留下了一个错误说

IntelliSense: argument of type "Occurrences **" is incompatible with parameter of type "Occurrences *"

这段代码：

maximum_occurrences(str, ch, num, arr1);

位于我的main.c。我将尝试提供下面所需的所有代码。关于如何在最后修复崩溃的任何想法都将非常感激，但程序逻辑再次完美！ :)谢谢我也是一个新手编码器（C学期一个学期）。

主：

int main ()
{
    // Introduced the original string which as a pointer.
    // Introduced the original character pointer 'ch'. (Set to an arbitrary Character.)
    // Introduced the original int pointer as 'num'. (Set to an arbitrary integer.)
    char *str = {"hey my name is dillon johnson im in comp sci"}, *ch = '\0';
    int *num = 0;

    struct Occurrences *arr1[25];

    // Calling the max occurrences function.
    maximum_occurrences(str, ch, num, arr1);

    return 0; 
}

部首：

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

typedef struct occurrences
{
    int num_occurrences;
    double frequency;
}Occurrences;

void maximum_occurrences (char *str, char *chPtr, int *num, Occurrences *arr1);

由source.c：

void maximum_occurrences(char *str, char *chPtr, int *num, Occurrences *arr1)
{
    char stringp = *str;
    int i = 0, j = 0, strLength = 0, temp, max = 0, k = 0;
    double frequency = 0;
    char maxch = ' ';

    // Setting strLength to the length of the alpha string.
    strLength = strlen(str);

    for (k = 0; k < 25; k++)
    {
        arr1[k].num_occurrences = 0;
    }

    // Displaying to the user what sentance will be used for the program.
    printf ("%s%s", "The given sentence is: ", str);
    printf ("\n");

    // The algorithm to determine which characters occur multiple times.
    // I am using a for loop to first parse through the array and then when
    // each letter occurs I subtract 97 from the ascii value. The resulting
    // Integer will be the corresponding place in the array of struct Occurrences
    // where that particular variable is held.

    for (i = 0; i < strLength; i++)
    {
        temp = (str[i] - 97); // temp is now set to an integer value that is the correspoinding position in the array of structs.
        (int)arr1[temp].num_occurrences = (int)arr1[temp].num_occurrences + 1; // Increases the number of occurrences in the specific struct by one to represnt
                                                                     // a single occurrence of that character.
    }

    for (j = 0; j < 26; j++)                    // This finds the maximum amount of occurrences and then continues to mach that value
    {                                           // to a character by adding 97 to the index of the array to acheive the appropriate ascii value
        if (max < arr1[j].num_occurrences)
        {
            max = arr1[j].num_occurrences;
            maxch = j + 97;
        }
    }

    frequency = ((double)max / (double)strLength); // Calculating the frequency of the most common character

    printf ("%s%c%s%d%s%.3lf%s", "The letter '", maxch,"' occurred the most, occurring ", max, " times, with a frequency of: ", frequency,".\n");

    return;
}

Answer 1

问题正是错误消息告诉你的。学会解释编译错误，生活对你来说会更容易......

arr1是一个包含20个指向Occurrences结构的指针的数组。

maximum_occurrences需要一个Occurrences*，而不是它们的数组。

因此，您无法将arr1传递给maximum_occurrences()。

根据评论讨论：

在main（）中你有struct Occurrences* arr1[25]; - 一个包含25个指向事件的数组（Occurrences *）。你永远不会分配任何出现次数，所以即使它确实编译了，它也不会起作用。

你想要25次出现（不是指针） - struct Occurrences arr1[25]; - 现在你应该可以按原样使用max_occurrences了。请注意，让max_occurrences假设长度为25是不好的做法 - 您应该将长度传递给它。

最后但并非最不重要的是，如果你想要每个字母出现1次，你需要一个26的数组（它给你的索引0-25）

Answer 2

您需要将功能更改为

void maximum_occurrences(char *str, char *chPtr, int *num, Occurrences **arr1, int arrsize){
//..
for (k = 0; k < arrsize; k++)
    {
        arr1[k]->num_occurrences = 0;
    }
//..
for (j = 0; j < arrsize; j++)                    // This finds the maximum amount of occurrences and then continues to mach that value
    {                                           // to a character by adding 97 to the index of the array to acheive the appropriate ascii value
        if (max < arr1[j]->num_occurrences)
        {
            max = arr1[j]->num_occurrences;
            maxch = j + 97;


       }
        //..
}

然后用

调用它

maximum_occurrences(str, ch, num, arr1, 25);

另外，在使用arr1为每个数组元素调用maximum_occurrences()之前，不要忘记为malloc(sizeof(struct Occurrences))分配内存。

结构数组：不兼容的参数类型

2 个答案: