无法将函数的指针值返回到 main

Question

程序问题链接https://www.hackerrank.com/challenges/cut-the-sticks/problem

#include <assert.h>
#include <limits.h>
#include <math.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

char* readline();
char** split_string(char*);

 int* cutTheSticks(int arr_count, int* arr, int* result_count) {
int c=arr_count,min;
int result[c];
for (int k=0;k<arr_count;k++){
    min = *arr;
    for (int i = 0; i < c; i++) {
    if (*(arr + i) < min)
      min = *(arr + i);
    }
    int count=0;
    for (int i=0; i < c; i++) {
        if(min==*(arr+i))count++;
    }

    for (int i=0; i < c; i++) {
        *(arr+i)=*(arr+i)-min;
    }
    int temp=0;
    for(int i=0;i<c;i++){
        for(int x=i;x<c;x++){
            if(*(arr+i)<*(arr+x)){
                temp=*(arr+i);
                *(arr+i)=*(arr+x);
                *(arr+x)=temp;
            }
        }
    }
    result[k]= c;
        *(result_count)=*(result_count)+1;
    c = c - count;
    if(c==0)break;
}
return result;
 }

int main()
 {
FILE* fptr = fopen(getenv("OUTPUT_PATH"), "w");

char* n_endptr;
char* n_str = readline();
int n = strtol(n_str, &n_endptr, 10);

if (n_endptr == n_str || *n_endptr != '\0') { exit(EXIT_FAILURE); }

char** arr_temp = split_string(readline());

int* arr = malloc(n * sizeof(int));

for (int i = 0; i < n; i++) {
    char* arr_item_endptr;
    char* arr_item_str = *(arr_temp + i);
    int arr_item = strtol(arr_item_str, &arr_item_endptr, 10);

    if (arr_item_endptr == arr_item_str || *arr_item_endptr != '\0') { 
 exit(EXIT_FAILURE); }

    *(arr + i) = arr_item;
}

int arr_count = n;

int result_count;
int* result = cutTheSticks(arr_count, arr, &result_count);

for (int i = 0; i < result_count; i++) {
    fprintf(fptr, "%d", *(result + i));

    if (i != result_count - 1) {
        fprintf(fptr, "\n");
    }
}

fprintf(fptr, "\n");

fclose(fptr);

return 0;
}

char* readline() {
size_t alloc_length = 1024;
size_t data_length = 0;
char* data = malloc(alloc_length);

while (true) {
    char* cursor = data + data_length;
    char* line = fgets(cursor, alloc_length - data_length, stdin);

    if (!line) { break; }

    data_length += strlen(cursor);

    if (data_length < alloc_length - 1 || data[data_length - 1] == '\n') { 
    break; }

    size_t new_length = alloc_length << 1;
    data = realloc(data, new_length);

    if (!data) { break; }

    alloc_length = new_length;
}

if (data[data_length - 1] == '\n') {
    data[data_length - 1] = '\0';
}

data = realloc(data, data_length);

return data;
}

char** split_string(char* str) {
char** splits = NULL;
char* token = strtok(str, " ");

int spaces = 0;

while (token) {
    splits = realloc(splits, sizeof(char*) * ++spaces);
    if (!splits) {
        return splits;
    }

    splits[spaces - 1] = token;

    token = strtok(NULL, " ");
}

return splits;
}

上面的代码是我来自 harkerrank 的完整代码，下面是主要功能。 我无法将指针值从 cutTheStricks 返回到主函数。

// Please store the size of the integer array to be returned in
    result_count 
    pointer. For example,
// int a[3] = {1, 2, 3};
//
// *result_count = 3;
//
// return a;

int* cutTheSticks(int arr_count, int* arr, int* result_count) {
int c=arr_count,min;
int result[c];
for (int k=0;k<arr_count;k++){
    min = *arr;
    for (int i = 0; i < c; i++) {
    if (*(arr + i) < min)
      min = *(arr + i);
    }
    int count=0;
    for (int i=0; i < c; i++) {
        if(min==*(arr+i))count++;
    }

    for (int i=0; i < c; i++) {
        *(arr+i)=*(arr+i)-min;
    }
    int temp=0;
    for(int i=0;i<c;i++){
        for(int x=i;x<c;x++){
            if(*(arr+i)<*(arr+x)){
                temp=*(arr+i);
                *(arr+i)=*(arr+x);
                *(arr+x)=temp;
            }
        }
    }
    result[k]= c;
        *(result_count)=*(result_count)+1;
    c = c - count;
    if(c==0)break;
}
return result;

}

我没有得到任何输出，但我的逻辑是正确的。我知道缺少一些东西，因此我无法返回我的输出；我无法弄清楚哪个指针值(*result 或 *result_count )没有传递或者我无法弄清楚发生了什么。

Answer 1

您正在返回一个本地数组的地址，其生命周期以函数change结束

int result[c];

至

int *result = malloc(sizeof(*result) * c);

您还在此处使用未初始化值的地址:

*(result_count)=*(result_count)+1;

改变

int result_count;

至

int result_count = 0;