陣列結構的：不兼容的參數類型

Question

這是第一次我提出結構的數組。基本上我試圖做出一種直方圖。這是分析我提供的字符串，並打印出哪個字母出現次數最多。我也想說我的程序確實有效！我得到了所有正確的結果。但是當程序完成計算並顯示它們時，它會崩潰。而且我留下了一個錯誤，說

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

此行的代碼：

maximum_occurrences(str, ch, num, arr1); 

它位於我main.c。我會盡力提供下面所有必需的代碼。任何關於如何在最後修復崩潰的想法都將非常感激，但程序邏輯再次完美無缺！ :)也謝謝我是新手編碼器（C中的1個學期）。

主營：

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; 
} 

頁眉：

#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

的問題到底是什麼錯誤消息告訴你。學會解讀的編譯器錯誤和生活將是您更容易...

arr1是25個指針紀錄結構數組。

maximum_occurrences預計一個Occurrences*，不是他們的陣列。

因此，你不能傳遞到arr1maximum_occurrences()。

基於通過評論的討論：）

在main（你有struct Occurrences* arr1[25]; - 25個指針數組紀錄（紀錄*）。你從不分配任何事件，所以即使它編譯了，也不會起作用。

你想要25次發生（非指針） - struct Occurrences arr1[25]; - 現在你應該可以按原樣使用max_occurrences。請注意，max_occurrences假設長度爲25是不好的做法 - 您應該將長度轉換爲長度。

最後但並非最不重要的，如果你想每個字母出現1次，需要26的陣列（它給你的索引0-25）

Answer 2

你需要的功能更改爲

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; 


     } 
     //.. 
} 

然後調用它與

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

另外，不要使用調用maximum_occurrences()之前忘了分配的內存arr1 210用於每個數組元素。