爲什麼數組的元素不被計數？

Question

#include "stdafx.h" 
#include<stdio.h> 



int main (void) 
{ 

//第1部分。這工作完全正常

int array[20]; 
     int n; 
     for(n = 0; n <10; ++n) 
     { 
     array[n] = 0; 
    } 

    for(n = 10; n <20; ++n) 
    { 
     array[n]= n-9; 
    } 

    for(n = 4; n <10; ++n) 
    { 
     array[n]= array[n]+1; 
    } 

    for(n = 0; n < 20; ++n) 
    { 
     array[n] = array[n] * 3; 
    } 

    for(n=0; n < 20; ++n) 
    { 
     printf("%i \t" ,array[n]); 
    } 

//第2部分。這是我遇到的麻煩。我應該創建一個直方圖和一個//表格來統計每個響應。 1的總數，2的等，我只是得到100 1。 //爲什麼？

int array2[100] = {6, 7, 8, 9, 8, 7, 8, 9, 7, 8, 9, 8, 9, 8, 9, 5, 9, 8, 7, 8, 7, `8, 6, 7, 8`, 
9, 3, 9, 8, 7, 8, 9, 9, 8, 9, 8, 9, 8, 9, 7, 8, 9, 6, 7, 8, 7, 8, 7, 9, 7, 
6, 5, 3, 5, 6, 7, 2, 5, 3, 9, 4, 6, 4, 7, 8, 9, 6, 8, 7, 8, 9, 7, 8, 7, 4, 
4, 3, 6, 4, 6, 7, 5, 6, 4, 5, 6, 1, 6, 5, 7, 8, 5, 3, 6, 3, 5, 7, 5, 8, 9}; 
float sum=0.0; 
float average=0; 
int j, i,d; 
int max=0; 
int mode =0; 

for (n=0; n<100; ++n) 
    { 

     sum = sum + array2[n]; 
    } 
    //int average=0; 
     average= sum/100; 
    printf("\n\nThe mean of the responses in the array is %.2f", average); 
    int maxCount=0; 
     int modeValue; 
     int tally[100]={0}; 
    for (i = 0; i < 100; i++) 
    { 
     tally[array2[i]]++; 
    } 
    //maxCount = 0; 
    //modeValue = 0; 
    for (j = 0; j < 100; j++) 
    { 
     if (tally[j] > maxCount) 
     { 
      maxCount = tally[j]; 
      modeValue = j; 
     } 
    } 
    printf("\n\nThe mode is %i", modeValue); 

//我的問題是在這裏：爲什麼它都註冊爲1。我得到了100個。 //我在做什麼錯

int onecount=0; 
     int twocount=0; 
     int threecount=0; 
     int fourcount=0; 
     int fivecount=0; 
     int sixcount=0; 
     int sevencount=0; 
     int eightcount=0; 
     int ninecount=0; 

     for (d=0;d<100;d++) 
     { 
     if (array2[d] =1) 

       ++onecount; 

      else if (array2[d]=2) 

       ++twocount; 


      else if (array2[d]=3) 

       ++threecount; 


      else if (array2[d]=4) 

       ++fourcount; 


      else if (array2[d] =5) 

       ++fivecount; 


      else if(array2[d] =6) 

       ++sixcount; 


      else if(array2[d] =7) 

       ++sevencount; 


      else if(array2[d] =8) 

       ++eightcount; 


      else if(array2[d]=9) 

       ++ninecount; 
     } 

     int star=0; 

     printf("\n\nHistogram of of Survey responses:\n"); 
      printf("\n1's: "); 
      for(star=0; star<onecount; ++star) //print 1 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n2's : "); 
      for(star=0; star<twocount; ++star) //print 2part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n3's: "); 
      for(star=0; star<threecount; ++star) //print 3 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n4's: "); 
      for(star=0; star<fourcount; ++star) //print 4 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n5's : "); 
      for(star=0; star<fivecount; ++star) //print 5 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n6's: "); 
      for(star=0; star<sixcount; ++star) //print 6 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n7's: "); 
      for(star=0; star<sevencount; ++star) //print 7 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n8's : "); 
      for(star=0; star<eightcount; ++star) //print 8 part of histogram 
       { 
       printf("*"); 
       } 
      printf("\n9's: "); 
      for(star=0; star<ninecount; ++star) //print 9 part of histogram 
       { 
       printf("*"); 
       } 

      printf("\n\nTable of Survey Responses: \n\n"); 
      printf("1's: %i\t\t2's:%i\t\t3's:%i\t\t4's:%i\t\t5's:%i\t\t6's:%i\t\t7's:%i\t\t8's:%i\n\t\t9's:%i", onecount, twocount, threecount,fourcount,fivecount,sixcount,sevencount,eightcount,ninecount); 

     return 0; 
    } 

Answer 1

在此代碼：

if (array2[d] =1) 

     ++onecount; 

    else if (array2[d]=2) 

     ++twocount; 

您需要使用 '=='，而不是 '='，這是C.

賦值運算符

例如，

if(array2[d] == 1)