编译器的问题？ vb6.0 VS visual studio 2012 - C语言论坛

chihuyu

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已结贴√ 问题点数：6 回复次数：7

编译器的问题？ vb6.0 VS visual studio 2012

程序代码：

#include<stdio.h>
void main()
{
    int i=3,j=5;
    int *p,*q;
    p=&i;
    q=&j;

    float a=5.8,b=7.9;
    float *c,*d;
    c=&a;
    d=&b;

    char m='I',n='L';
    char *x,*y;
    x=&m;
    y=&n;

    printf("i=%d, j=%d\n",*p,*q);
    printf("a=%g, b=%g\n",*c,*d);
    printf("m=%c, n=%c\n",*x,*y);
}

以上很简单的一段代码，主要是试试用指针，在vb6.0里面可以实现，但是在ms visual studio 2012里面，就不行
编译不通过

1>------ Build started: Project: Have a try, Configuration: Debug Win32 ------
1> Have a try.c
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(9): error C2143: syntax error : missing ';' before 'type'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(10): error C2143: syntax error : missing ';' before 'type'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(11): error C2065: 'c' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(11): error C2065: 'a' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(11): warning C4047: '=' : 'int' differs in levels of indirection from 'int *'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(12): error C2065: 'd' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(12): error C2065: 'b' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(12): warning C4047: '=' : 'int' differs in levels of indirection from 'int *'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(14): error C2143: syntax error : missing ';' before 'type'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(15): error C2143: syntax error : missing ';' before 'type'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(16): error C2065: 'x' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(16): error C2065: 'm' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(16): warning C4047: '=' : 'int' differs in levels of indirection from 'int *'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(17): error C2065: 'y' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(17): error C2065: 'n' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(17): warning C4047: '=' : 'int' differs in levels of indirection from 'int *'
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(20): error C2065: 'c' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(20): error C2100: illegal indirection
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(20): error C2065: 'd' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(21): error C2065: 'x' : undeclared identifier
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(21): error C2100: illegal indirection
1>c:\users\dell\documents\visual studio 2012\projects\have a try\have a try\have a try.c(21): error C2065: 'y' : undeclared identifier
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

请问大家，这是为什么呀？
如果将程序代码改成

程序代码：

#include<stdio.h>
void main()
{
    int i=3,j=5;
    int *p,*q;
    float a=5.8,b=7.9;
    float *c,*d;
    char m='I',n='L';
    char *x,*y;

    p=&i;
    q=&j;

    c=&a;
    d=&b;

    x=&m;
    y=&n;

    printf("i=%d, j=%d\n",*p,*q);
    printf("a=%g, b=%g\n",*c,*d);
    printf("m=%c, n=%c\n",*x,*y);
}