int pointer & char pointer

#include <iostream>

using namespace std;

void main()

{

    //int *iPtr = NULL;

    //iPtr = 5; //编译错误：error C2440: “=”: 无法从“int”转换为“int *”

    ////*iPtr = 5; // xxx.exe 中的 0x004113e8 处未处理的异常: 
    ////0xC0000005: 写入位置 0x00000000 时发生访问冲突

    //cout << iPtr << endl;

    //int *iPtr2;

    //*iPtr2 = 3; // Run-Time Check Failure #3 
    ////- The variable 'iPtr2' is being used without being initialized.

    char *cPtr = NULL;

    cPtr = "a";

    printf("%x\n", cPtr);

    cout << cPtr << endl;

    char *cPtr2;

    cPtr2 = "b";

    printf("%x\n", cPtr2);

    cout << cPtr2 << endl;

    /*

    417808

    a

    417800

    b

    请按任意键继续. . .

    */

}