C 使用嵌套循环计算年降雨量总量，并匹配用户输入

Question

我很难理解为什么我的程序无法正确执行。我需要使用循环计算每年的总降雨量，我遇到的问题是它不排除 2 月份的用户输入，而是添加前几年的总降雨量(即 2011 年总降雨量变为 2012 年 2 月用户输入)。任何帮助将不胜感激。

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


#define NUMMONTHS 12
#define NUMYEARS 5

// function prototypes
void inputdata();
void printdata();

// Global variables
// These are available to all functions
float Raindata[NUMYEARS][NUMMONTHS];
float sum = 0.0;
char years[NUMYEARS][5] = {"2011","2012","2013","2014","2015"};
char months[NUMMONTHS][12] =
   {"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};

int main ()
{
    char enterData = 'y';
    printf("Do you want to input Precipatation data? (y for yes)\n");
    scanf("%c",&enterData);
    if (enterData == 'y') {
        // Call Function to Input data
        inputdata();

        // Call Function to display data
        printdata();
    }
    else {
        printf("No data was input at this time\n");
    }
    printf("Please try the Precipitation program again. \n");

    return 0;
}

// function to inputdata
void inputdata() {
    /* variable definition: */
    float Rain=1.0;
    // Input Data
    for (int year=0;year < NUMYEARS; year++) {
       for (int month=0; month< NUMMONTHS; month++) {
         printf("Enter rain for %d, %d:\n", year+1, month+1);
         scanf("%f",&Rain);
         Raindata[year][month]=Rain;
       }
    }
}

// Function to printdata
void printdata()
{
    // Print data
    printf ("year\t month\t rain\n");

    //Function to sum rainfall 
    for (int year=0; year< NUMYEARS; year++) {
        for (int month=0; month< NUMMONTHS; month++) {
              printf("%s\t %s\t %5.2f\n", 
                years[year],months[month],Raindata[year][month]);
             Raindata[year][NUMMONTHS+1] += Raindata[year][month]; 
        }
        printf("Total amount of rain for year %s: %5.2f\n", years[year], 
               Raindata[year][NUMMONTHS+1]); //prints the total amount of rain every year 
    }
}

这是输出:

Total amount of rain for year 2011: 40.00
2012     Jan      1.10
2012     Feb     40.00
2012     Mar      3.30

Answer 1

主要问题是您试图将每年的总计存储在一个不存在的变量中 - 一个额外的数组元素 Raindata[year][month+1]。您只声明了一个 5x12 数组，并且尝试将其用作 5x13 数组。由于数组在内存中的存储方式，您将[month+1] 值存储在下一年的数据中。

相反，我添加了一个额外的数组 (RainTotal[NUMYEARS])，并用它来存储每年的总计。

#include <stdio.h>


#define NUMMONTHS 12
#define NUMYEARS 5


// function prototypes
void inputdata(void);
void printdata(void);


// Global variables
// These are available to all functions
float Raindata[NUMYEARS][NUMMONTHS];
float RainTotal[NUMYEARS];
float sum = 0.0;
char years[NUMYEARS][5] = {"2011","2012","2013","2014","2015"};
char months[NUMMONTHS][4] =
  {"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};

int main ()
  {
    char enterData = 'y';
    printf("Do you want to input Precipatation data? (y for yes)\n");
    scanf("%c",&enterData);

    if (enterData == 'y') {
      // Call Function to Input data
      inputdata();


      // Call Function to display data
      printdata();
    }
    else {
      printf("No data was input at this time\n");
    }

    printf("Please try the Precipitation program again. \n");

    return 0;
  }

// function to inputdata
void inputdata() {
  // variable definition
  float Rain=1.0;
  // Input Data
  for (int year=0;year < NUMYEARS; year++) {
    for (int month=0; month< NUMMONTHS; month++) {
      printf("Enter rain for %s, %s:\n", years[year], months[month]);
      scanf("%f",&Rain);
      Raindata[year][month]=Rain;
    }
  }
}

// Function to printdata
void printdata() {
  // Print data
  printf ("year\t month\t rain\n");

  //Function to sum rainfall
  for (int year=0; year< NUMYEARS; year++) {
    for (int month=0; month< NUMMONTHS; month++) {
      printf("%s\t %s\t %5.2f\n",
        years[year],months[month],Raindata[year][month]);
        RainTotal[year] += Raindata[year][month];
    }
    printf("Total amount of rain for year %s: %5.2f\n", years[year],
      RainTotal[year]); //prints the total amount of rain every year
  }
}

我还做了一些其他更改:

• 您声明了年和月，第二个数组元素似乎等于年数和月数。相反，它应该是 char 字符串的预期长度加上 1(对于空终止符)。

• 我更改了您的打印语句以显示您声明的字符串，因此 Enter rain for 2011, Jan: 而不是 Enter rain for 1, 1:

• 我修复了您的函数原型(prototype)(其他用户也指出了)

• 清理了您的格式 - 查看一些流行的编码标准 - 当您请求他人帮助时，这将使您的代码更具可读性:)