diff options
-rw-r--r-- | 3.6.c | 62 |
1 files changed, 62 insertions, 0 deletions
@@ -0,0 +1,62 @@ +#include <stdio.h> + +#define MAXLEN 25 + +void reverse(char str[]); +char* itoa(int n, char str[], int fieldwidth); + +int +main(void) +{ + int n = 214748; + char str[MAXLEN]; + + printf("%d\n", n); + printf("%s\n", itoa(n, str, 10)); + + return 0; +} + +void +reverse(char str[]) +{ + int i, j; + char temp; + + for (j = 0; str[j] != '\0'; j++) + ; + + for (i = 0, --j; i < j; i++, j--) { + temp = str[i]; + str[i] = str[j]; + str[j] = temp; + } +} + +char* +itoa(int n, char str[], int fieldwidth) +{ + int sign, i; + + /* to include the most -ve int */ + n = ((sign = n) < 0) ? -(n+1) : n-1; + + i = 0; + do { + str[i++] = n%10 + '0'; + } while ((n /= 10) > 0); + + if (sign <0) + str[i++] = '-'; + + while (i < fieldwidth) + str[i++] = ' '; + + /* part of "to include the most -ve int" */ + str[0] += 1; + str[i] = '\0'; + + reverse(str); + + return str; +} |