我在运行代码时遇到错误，该代码接受用户的温度并以相反的顺序打印，为什么会这样？-解网

问：

我正在编写这段代码，作为家庭作业，以满足以下要求：

（不允许使用函数 realloc）

最初分配一个阵列以容纳多达 5 个温度。
提示用户输入温度，并在输入完成后键入值 -100.0。
如果用户填满了数组，您的程序应该动态分配一个大小翻倍的新数组。
将旧值复制到新数组中。解除分配旧数组。
继续读取新数组。

读取完数组后，程序应像以前一样，以 1 个小数点的精度反向（从最近到最旧）输出温度读数，并在输入末尾换行

这是我的方法：

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

int main(void)
{
int size = 5;
float *temperature_first = malloc(sizeof(float)*size);
float *temperature_second;
float inputArray;
int switch_array = 0;
int count = 0;

printf("'Please enter temperature; type '-100' to end: ");
while(inputArray !=-100){

  while((inputArray != -100)&&(count<=size)){
    if(switch_array==0){

      scanf("%f", &temperature_first[count]);
      inputArray = temperature_first[count];
    }

    else{
      scanf("%f", &temperature_second[count]);
      inputArray = temperature_second[count];
    }
    count++;
    }
    if((count>=size)){

      size  = size*2;

      if(switch_array==0){
      temperature_second = malloc(sizeof(float)*size);
      for(int elements = 0;elements<(size/2)+1;elements++){

        temperature_second[elements] = temperature_first[elements];
      }
        free(temperature_first);

        switch_array = 1;
      }
      else{
        temperature_first = malloc(sizeof(float)*size);
        for(int elements = 0;elements<(size/2)+1;elements++){

          temperature_first[elements] = temperature_second[elements];

        }

          free(temperature_second);

          switch_array = 0;
    }
  }
}
for(int i = count-2;i>-1;i--){
  if(i==0){
  if(switch_array==0)
  {
    printf("%0.1f", temperature_first[i]);
   }
   else{
     printf("%0.1f", temperature_second[i]);
   }
  }
  else{
    if(switch_array==0){
      printf("%0.1f ", temperature_first[i]);
    }
    else{
      printf("%0.1f ", temperature_second[i]);
    }
  }
}
printf("\n");

if(switch_array==0){
  free(temperature_first);
}
else{
  free(temperature_second);
}
return 0;
 }

运行特定测试时：输入： 16.5 18.8 20.5 21.3 16.2 15.0 17.0 19.7 21.2 56.3 12.5 44.5

以下行用于编译：

gcc -Wall -Werror=vla -std=c11 -o temperatures02 temperatures02.c

这是我遇到的：

malloc(): corrupted top size
Aborted (core dumped).

我不太确定为什么。

任何帮助将不胜感激。

谢谢！

阵列 C 动态 malloc

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

int main(void)
{
  int size = 5;
  float *temperatures = malloc(sizeof(float)*size); // TODO: Check for NULL
  float temperature;
  int count = 0;

  printf("Please enter temperature; type '-100' to end: ");
  scanf("%f", &temperature);
  // TODO: Check result for error!

  while (temperature != -100) {
    temperatures[count] = temperature;
    count++;

    if (count == size) {
      size *= 2;
#if DO_IT_LIKE_THE_TASK_DEMANDS_IT
      float *newarray = malloc(sizeof(float)*size);
      // TODO: Check for NULL!
      for (int i = 0; i < count-1; i++) {
        newarry[i] = temperatures[i];
      }
      free(temperatures);
#else
      float *newarray = realloc(temperatures, sizeof(float)*size);
      // TODO: Check for NULL!
#endif
      temperatures = newarray; 
    }

    printf("Please enter temperature; type '-100' to end: ");
    scanf("%f", &temperature);
    // TODO: Check result for error!
  }

  // Print them backwards (not in the task but in your code
  // Last element was put into temperatures[count] before we did count++.
  // Therefore now we need to start at index count-1, not count-2

  for(int i = count-1;i>-1;i--) {
    if (i==0) {
      printf("%0.1f", temperatures[i]);
    }
    else {
      printf("%0.1f ", temperatures[i]);
    }
  }
  printf("\n");

  free(temperatures);
  return 0;
 }

在 https://www.onlinegdb.com/online_c_compiler 展会上测试：

Please enter temperature; type '-100' to end: 16.5
Please enter temperature; type '-100' to end: 18.8
Please enter temperature; type '-100' to end: 20.5
Please enter temperature; type '-100' to end: 21.3
Please enter temperature; type '-100' to end: 16.2
Please enter temperature; type '-100' to end: 15.0
Please enter temperature; type '-100' to end: 17.0
Please enter temperature; type '-100' to end: 19.7
Please enter temperature; type '-100' to end: 21.2
Please enter temperature; type '-100' to end: 56.3
Please enter temperature; type '-100' to end: 44.5
Please enter temperature; type '-100' to end: -100
44.5 56.3 21.2 19.7 17.0 15.0 16.2 21.3 20.5 18.8 16.5


...Program finished with exit code 0

上一个：如何在没有 malloc oder calloc 的情况下给出指针元素

下一个：malloc 的默认值是否为单个字符 P 的大小？

我在运行代码时遇到错误，该代码接受用户的温度并以相反的顺序打印，为什么会这样？

I am running into an error while running my code, which accepts temperatures from user and prints in reverse order, why is that so?

评论