c - 我的多维数组程序没有正确填充,我错过了什么?
问题描述
我正在为类编写一个程序,该程序从文本文件中对一组数字进行排序,并输出最高降雪量、第二高降雪量和总降雪量范围。
它的工作,主要是。但是我在输出正确的英寸数和第二高降雪量的程序时遇到了问题。
那个 .txt 文件里面有这个
2017 180.00
2016 176.50
2015 181.50
2014 208.75
2013 225.75
2012 132.00
2011 178.50
2010 150.50
2009 217.00
2008 185.25
2007 162.75
2006 219.50
2005 164.71
2004 232.00
2003 228.00
2002 254.00
2001 303.60
2000 155.00
1999 231.00
1998 131.50
1997 253.10
1996 328.20
1995 175.90
1994 185.30
1993 159.60
1992 166.20
1991 165.80
//Block comment with name, date, program description
#include <stdlib.h>
#include <stdio.h>
// include other header files that you need
#define MAX_SIZE 100 //can go back 100 years if necessary
#define t 1
#define num 20
int ReadFile (int data1[], double data2[]);
int HighestSnow(double data[], int size);
int NextHighestSnow (double data[], int size, int Highest);
double Range (double data[], int size);
int main (void)
{
int Year[MAX_SIZE];
double Snow[MAX_SIZE],SnowfallRange;
int FileLength, IndexHighest, IndexNextHighest;
int i;
//Describe code
//Read file using function
FileLength = ReadFile(Year,Snow);
for(i = 0; i < FileLength; i++)
printf("The year for the highest snowfall is: [%d] at %lg\n", Year[IndexHighest], Snow[IndexHighest]);
//Print out data in two columns with first being year and second
//being snowfall in inches
IndexHighest = HighestSnow(Snow,FileLength);
printf("The year for the highest snowfall is: [%d] at %lg\n", Year[IndexHighest], Snow[IndexHighest]);
//Print out the year and amount of the highest snowfall
IndexNextHighest = NextHighestSnow(Snow, FileLength, IndexHighest);
printf("The year for the second highest snowfall is: [%d] at %lg\n", Year[IndexNextHighest], Snow[IndexNextHighest]);
//Print out the year and amount of the next highest snowfall
SnowfallRange = Range(Snow,FileLength);
printf("The snow range is: %lg\n", SnowfallRange);
//Print out the range of snowfall (Max-Min) in inches.
return 0;
}
//Code for part 1 goes here, include ALL error checks.
int ReadFile (int data1[], double data2[])
{
FILE *f; //Step 1: Declaring a file pointer
f = fopen("snowfall.txt", "r"); //Step 2: opening a file
if(f == NULL) //Step 3: checking to see if the file exists
{
printf("File does not exit\n");
exit(1);
}
int i;
for(i = 0; fscanf(f,"%d %lf ", &data1[i], &data2[i]) == 2; i++); //Step 4: read the values
fclose(f);
return i;
}
// Code for part 2 goes here
int HighestSnow(double data[], int size)
{
int i, index;
double max = data [0];
for (i = 1; i < size; i++)
{
if (data[i] > max)
{
max = data[i];
index = i;
}
}
return index;
}
/* Code for part 3 goes here*/
int NextHighestSnow(double data[], int size, int Highest)
{
int i;
double secmax = -1;
int arrayindex;
for(i = 0; i > size; i++)
{
if(data[i] > secmax && data[i] < Highest) {
secmax = data[i];
arrayindex = i;
}
}
return arrayindex;
}
/* Code for part 4 goes here*/
double Range (double data[], int size)
{
double maxval = data[HighestSnow(data, size)];
double min = data[0];
int i;
for(i = 1; i < size; i++)
{
if(min > data[i])
min = data[i];
}
return maxval - min;
}
问题:文件“snowfall.txt”中提供了密歇根州过去 20 年的总降雪量(以英寸为单位)。该文件的格式设置为第一列是年份,第二列是该年的降雪量(以英寸为单位)。编写程序获取以下信息: 1. 哪一年降雪量最大,那一年降了多少(英寸)?2. 降雪量第二高的年份是哪一年,那一年降了多少(英寸)?3. 过去 20 年的总降雪量范围是多少?除非另有说明,否则所有 printf 语句都必须在 main() 中。注意:请记住,您可以使用 EXCEL 验证您的结果。请遵循以下详细说明: 1. 首先,完整阅读本文档。2. 包括通常的(详细)注释块,包括程序名称、作者、日期、输入、输出和描述,然后是您的预处理器指令。3. 源代码的大纲(骨架代码)如下所示,您需要遵循此大纲。你可以编写其他支持函数,但你必须至少有 4 个函数原型。在需要的地方插入适当的 printf 语句以获得所需的输出。大纲有四个部分,您可以在其中输入代码并完成程序。一个。第 1 部分:您需要编写函数 ReadFile 以打开“snowfall.txt”进行输入,并将该文件中的数据读入 2 个数组。记得检查文件是否存在并且没有读过 EOF。如果文件不存在的错误消息可以在函数中。该函数将返回文件中数据点的数量。注意:记住,数据是成对的,第一个数字是一年,第二个是降雪记录,以英寸为单位。从 main() 中打印出两列中的数据。湾。第 2 部分:您需要编写名为 HighestSnow 的函数,该函数接受降雪量数组,以及一个名为 size 的参数,该参数指示数组的大小。此函数返回一个整数,指示与最高降雪量对应的数组索引号。从 main() 中打印出最高降雪的年份和数量。C。第 3 部分:您需要编写函数调用 NextHighestSnow,它接受降雪量数组,一个名为 size 的参数指示数组的大小,一个名为 Highest 的整数指示对应于最高降雪量的索引。此函数返回一个整数,指示与第二大降雪量对应的数组索引号。从 main() 中打印出第二大降雪的年份和数量。d。第 4 部分:您需要编写函数调用 Range,它接受降雪量数组,以及一个名为 size 的参数,它指示数组的大小。此函数返回过去 20 年最大降雪量和最小降雪量之间的差值。请记住,您可以从 Range 函数调用 HighestSnow 函数。从 main() 打印出以英寸为单位的降雪范围。e. 第 5 部分(额外学分):让您的文件名成为用户输入,即询问用户输入的文件名。您需要编写函数调用 Range,它接受降雪量数组,以及一个名为 size 的参数,该参数指示数组的大小。此函数返回过去 20 年最大降雪量和最小降雪量之间的差值。请记住,您可以从 Range 函数调用 HighestSnow 函数。从 main() 打印出以英寸为单位的降雪范围。e. 第 5 部分(额外学分):让您的文件名成为用户输入,即询问用户输入的文件名。您需要编写函数调用 Range,它接受降雪量数组,以及一个名为 size 的参数,该参数指示数组的大小。此函数返回过去 20 年最大降雪量和最小降雪量之间的差值。请记住,您可以从 Range 函数调用 HighestSnow 函数。从 main() 打印出以英寸为单位的降雪范围。e. 第 5 部分(额外学分):让您的文件名成为用户输入,即询问用户输入的文件名。
OUTLINE OF THE SOURCE CODE:
//Block comment with name, date, program description
#include <stdio.h>
// include other header files that you need
#define MAX_SIZE 100 //can go back 100 years if necessary
int ReadFile (int data1[], double data2[]);
int HighestSnow (double data[], int size);
int NextHighestSnow (double data[], int size, int Highest);
double Range (double data[], int size);
int main (void) {
int Year[MAX_SIZE];
double Snow[MAX_SIZE],SnowfallRange;
int FileLength, IndexHighest, IndexNextHighest;
//Describe code
//Read file using function
FileLength = ReadFile(Year,Snow);
//Print out data in two columns with first being year and second
//being snowfall in inches
IndexHighest = HighestSnow(Snow,FileLength);
//Print out the year and amount of the highest snowfall
IndexNextHighest = NextHighestSnow(Snow, FileLength,IndexHighest);
//Print out the year and amount of the next highest snowfall
SnowfallRange = Range(Snow,FileLength);
//Print out the range of snowfall (Max-Min) in inches.
return 0;
}
//Code for part 1 goes here, include ALL error checks.
// Code for part 2 goes here
// Code for part 3 goes here
// Code for part 4 goes here
解决方案
我已经完成并指出了我发现的错误。
// Missing 3rd parameter
int NextHighestSnow (double data[], int size, int Highest);
// There is no 3rd parameter to range
double Range (double data[], int size);
int main (void)
{
// This should not be 2d
int Year[MAX_SIZE];
...
// Don't use %d to print a double. Use %lf, %le, %lg
printf("The year for the highest snowfall is: [%d] at %lg\n", Year[IndexHighest], Snow[IndexHighest]);
....
}
// Changed for 1d array
// Also, this should take a 3rd parameter for size....
int ReadFile (int data1[], double data2[])
{
....
// Changed test to == 2. fscanf returns # of items successfully scanned
// or EOF
for(i = 0; fscanf(f,"%d %lf ", &data1[i], &data2[i]) == 2; i++);
....
}
int HighestSnow(double data[], int size)
{
...
double max = data [0];
// Since you set max = data[0], loop can start at 1
for (i = 1; i < size; i++)
....
}
// Added 3rd param
int NextHighestSnow(double data[], int size, int Highest)
{
...
// Why search for min?
// Can't initialize to data[0] in case data[0] is max
// Use -1 since can't have negative snowfall
double secmax = -1;
int arrayindex;
for(i = 0; i > size; i++)
{
if(data[i] > secmax && data[i] < Highest) {
secmax = data[i];
arrayindex = i;
}
}
return arrayindex;
}
double Range (double data[], int size)
{
// Already have code to find max
double maxval = data[HighestSnow(data, size)];
double min = data[0];
int i;
for(i = 1; i < size; i++)
{
if(min > data[i])
min = data[i];
}
return maxval - min;
}