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#include "stdio.h"
void mscanf(char *format, ...)
{
scanf(format);
}
int main()
{
int n1, n2;
mscanf("%d%d", &n1, &n2);
printf("%d,%d\n", n1, n2);
return 0;
}
/***
*scanf.c - read formatted data from stdin
*
* Copyright (c) Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines scanf() - reads formatted data from stdin
*
*******************************************************************************/
#include <cruntime.h>
#include <stdio.h>
#include <dbgint.h>
#include <stdarg.h>
#include <file2.h>
#include <internal.h>
#include <mtdll.h>
/***
*int vscanf(format, ...) - read formatted data from stdin
*
*Purpose:
* This is a helper function to be called from fscanf & fscanf_s
*
*Entry:
* INPUTFN inputfn - scanf & scanf_s pass either _input_l or _input_s_l
* which is then used to do the real work.
* char *format - format string
* va_list arglist - arglist of output pointers
*
*Exit:
* returns number of fields read and assigned
*
*Exceptions:
*
*******************************************************************************/
int __cdecl vscanf (
INPUTFN inputfn,
const char *format,
_locale_t plocinfo,
va_list arglist
)
/*
* stdin 'SCAN', 'F'ormatted
*/
{
int retval;
_VALIDATE_RETURN( (format != NULL), EINVAL, EOF);
_lock_str2(0, stdin);
__try {
retval = (inputfn(stdin, format, plocinfo, arglist));
}
__finally {
_unlock_str2(0, stdin);
}
return(retval);
}
/***
*int scanf(format, ...) - read formatted data from stdin
*
*Purpose:
* Reads formatted data from stdin into arguments. _input_l does the real
* work here.
*
*Entry:
* char *format - format string
* followed by list of pointers to storage for the data read. The number
* and type are controlled by the format string.
*
*Exit:
* returns number of fields read and assigned
*
*Exceptions:
*
*******************************************************************************/
int __cdecl scanf (
const char *format,
...
)
{
va_list arglist;
va_start(arglist, format);
return vscanf(_input_l, format, NULL, arglist);
}
int __cdecl _scanf_l (
const char *format,
_locale_t plocinfo,
...
)
{
va_list arglist;
va_start(arglist, plocinfo);
return vscanf(_input_l, format, plocinfo, arglist);
}
/***
*int scanf_s(format, ...) - read formatted data from stdin
*
* Same as scanf above except that it calls _input_s_l to do the real work.
* _input_s_l has a size check for array parameters.
*
*******************************************************************************/
int __cdecl scanf_s (
const char *format,
...
)
{
va_list arglist;
va_start(arglist, format);
return vscanf(_input_s_l, format, NULL, arglist);
}
int __cdecl _scanf_s_l (
const char *format,
_locale_t plocinfo,
...
)
{
va_list arglist;
va_start(arglist, plocinfo);
return vscanf(_input_s_l, format, plocinfo, arglist);
}
va_list args;
va_start(args, format);
vscanf(format, args);
va_end(args);
#define mscanf scanf
方法二:
使用va_list, va_start, va_end, va_arg等宏,参考我刚写的这篇(我只实现了printf),你可以修改一下就能用。#include <stdarg.h>
/* 函数名:max
* 功能:返回n个整数中的最大值
* 参数:num:整数的个数 ...:num个输入的整数
* 返回值:求得的最大整数
*/
int MyMax ( int num, ... )
{
int m = -0x7FFFFFFF; /* 32系统中最小的整数 */
va_list ap;
va_start ( ap, num );
for ( int i= 0; i< num; i++ )
{
int t = va_arg (ap, int);
if ( t > m )
{
m = t;
}
}
va_end (ap);
return m;
}
int _tmain(int argc, _TCHAR* argv[])
{
int n = MyMax ( 5, 5, 6 ,3 ,8 ,5); /* 求5个整数中的最大值 */
cout << n << endl;
return 0;
}