《c 和指针》第9章第16题——数字字符串格式化输出

#include <stdio.h>#include <stdlib.h>#include <string.h>int format(char *format_string,char const *digit_string){char *p = format_string + strlen(format_string);char *p2 = (char *)digit_string + strlen(digit_string);char *flag = format_string;if(*digit_string == NULL)return 0;while(*flag!= 0){if(*flag == '.')break;flag++;}for(;p2 >= digit_string && p >= format_string;){if(*--p == '#'){*p = *--p2;}}while(p != format_string - 1){if(*flag != 0){while(p >= flag - 1){if(*p == '#')*p = '0';--p;}}*p-- = 1;}puts(format_string);return 1;}int main(void){char str[] = "###,###,###.##";char str1[] = "2343";format(str,str1);system("pause");return 0;}