C 程序显示一个正方形而不是字符串

Question

我已经用 Java 做了很多工作，但我目前正在尝试学习 c。我正在尝试编写一个程序将数字从十进制转换为二进制。

这是我的:

#include <stdio.h>
#define LENGTH 33

int main( int argc, char*argv[ ] )

{
 unsigned int number, base, remainder, x, i;
 char result[LENGTH];

 puts( "Enter a decimal value, and a desired base: " );
 scanf( " %u", &number );
 scanf( " %u", &base );

 x = number;

 for( i=0; i < LENGTH; i++ )
 {
  remainder = x % base;
  x = x/base;
  result[i] = remainder;
 }

 printf( "%u equals  %s  (base-%u) \n", number, result, base );    

 //***result is probably backwards...


 return 0;



}

这是我运行它时得到的结果:

Enter a decimal value, and a desired base: 
5 2
5 equals    (base-2) 

什么是正方形以及如何将其显示为字符串(字符数组)？

Answer 1

上次编辑:您的程序可能如下所示:

 unsigned int number, base, remainder, x, i;
 char result[LENGTH+1] = {0};

 puts( "Enter a decimal value, and a desired base: " );
 scanf( " %u", &number );
 scanf( " %u", &base );

 x = number;

 for( i=0; i < LENGTH; i++ )

 {
  // if base > 10, use alphabet!
  result[i] = remainder > 9 ? (remainder-10) + 'A' : remainder + '0';
  x = x/base;
  result[i] = remainder + '0';
 }

---

首先，在写余数的时候，要加上数字的ASCII偏移量。

  result[i] = remainder + '0';

还有，你忘了在最后添加'\0'。

 result[i] = 0;
 printf( "%u equals  %s  (base-%u) \n", number, result, base );

---

编辑:写入 C 字符串时，我通常将字符串初始化为零:

char result[LENGTH] = {0};

这样你就不需要在末尾写null character了，它是为你写的。

---

感谢@mmyers 指出溢出 :)我会声明要保存 LENGTH+1 的字符串:

char result[LENGTH+1] = {0};