你几乎在那里,虽然有几个错误,所以我已经“改进”了你的代码。无限循环测试只需要完成一次的基础。循环的while()
组织不完全正确 -x/b
在数字提取循环之外完成。我所做的另一项更改是使用查找数组将每个数字转换为字符,这样可以节省大量费力的测试。我还返回了作为函数值传递的字符串 - 不妨添加更多功能。在传递错误的基值的情况下,我本可以返回NULL
而不是空字符串。另请注意,我j
在将其用作索引的相同语句中进行了更新,这使代码更加流畅。
#include <stdio.h>
char *base_conversion (char *s, int x, int b) {
char charr[] = "0123456789ABCDEF";
int i, j = 0, len, digit, neg = 0;
*s = 0; // terminate the string passed
if (b < 2 || b > 16) // check the base
return s; // return an empty string
if (x < 0) {
x = -x; // adjust for negative input
neg = 1;
}
do {
digit = x % b; // extract each l.s. digit
s[j++] = charr [digit]; // convert to character
} while (x /= b); // implicitly test for 0
if (neg) // negative input
s[j++] = '-'; // append a minus sign
s[j] = 0; // terminate the string
// reverse the string
len = j;
for (i=0; i<len/2; i++) {
digit = s[i];
s[i] = s[--j]; // pre-decrement j to next char index
s[j] = digit;
}
return s;
}
int main () {
int n;
char strig[65];
for (n=1000; n>=-1000; n-=2000) {
printf ("Binary %d: %s\n", n, base_conversion (strig, n, 2));
printf ("Ternary %d: %s\n", n, base_conversion (strig, n, 3));
printf ("Octal %d: %s\n", n, base_conversion (strig, n, 8));
printf ("Decimal %d: %s\n", n, base_conversion (strig, n, 10));
printf ("Hexadecimal %d: %s\n", n, base_conversion (strig, n, 16));
}
return 0;
}
程序输出:
Binary 1000: 1111101000
Ternary 1000: 1101001
Octal 1000: 1750
Decimal 1000: 1000
Hexadecimal 1000: 3E8
Binary -1000: -1111101000
Ternary -1000: -1101001
Octal -1000: -1750
Decimal -1000: -1000
Hexadecimal -1000: -3E8