C语言：模拟实现printf函数——my_printf函数哦

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#define _CRT_SECURE_NO_WARNINGS 10#include<stdio.h>#include<stdarg.h>#include<stdlib.h>#include<assert.h>#include<string.h>//int printf( const char *format [, argument]... );//模拟实现printf函数，可以实现my_printf（“s ccc”，“hello”，‘b’，‘i’，‘t’）char *int_str(int nums){    char str[32] = "0";    int i = 0;    for (i = 31; i >= 0; i--)    {        str[i] = (nums & 1) + '0';        nums >>= 1;    }    printf("%s\n", str);}int my_printf(const char *format, ...){    assert(format);    va_list arg_list;    va_start(arg_list, format);    int count = 0;    const char *start = format;    while (*start != '\0')    {        if (*start == '%')        {            start++;            switch (*start)            {            case 's':            {                char *ret = va_arg(arg_list, char *);                fputs(ret, stdout);                count = count + strlen(ret);            }                break;            case 'c':            {                char _c = va_arg(arg_list, char);                putchar(_c);                count++;            }                break;            case 'd':            {                int _d = va_arg(arg_list, int);                char buf[10];                _itoa(_d, buf,10);                fputs(buf, stdout);                count = count + strlen(buf);            }                break;            case 'v':            {                int _dd = va_arg(arg_list, int);                char *array = int_str(_dd);                fputs(array, stdout);                count = count + strlen(array);            }                break;            }            start++;            continue;        }        putchar(*start);        start++;        count++;    }    va_end(arg_list);    return count;}int main(){    my_printf("%s %c%c%c", "hello", 'b', 'i', 't');    system("pause");    return 0;}
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