关于C++的一个小问题(循环方面)

当city数组中的字符串数与数据相同时会显示，但是当字符串数小于数据时则不会进入循环体，但是循环的判断条件为true，但是不执行里面的语句，以下代码是我测试的

#include <stdio.h>
#include <iostream>
const int Cities = 5;
const int Years = 4;
int main()
{
    using namespace std;
    const char* cities[Cities] = 
    {
        "Gribble City",
        "Gribbletown",
        //"New Gribble",
        //"San Gribble",
        "Gribble Vista"
    };

    int maxtemps[Years][Cities] = {
        {96, 100, 87, 101, 105},
        {96, 98, 91, 107, 104},
        {97, 101, 93, 108, 107},
        {98, 103, 95, 109, 108}
    };

    cout << "Maximum tempertures for 2008 - 2011\n\n";
    for (int city = 0; city < Cities; ++city)
    {
        if (city == 4)
            cout << "You have found me." << endl;
        cout << cities[city] << ":\t";

        for (int year = 0; year < Years; year++)   
            cout << maxtemps[year][city] << "\t";
            cout << endl;
    }

    system("pause");
    return 0;
}

实际只输出前三个数组的数据

#include <stdio.h>
#include <iostream>
const int Cities = 5;
const int Years = 4;
int main()
{
    using namespace std;
    const char* cities[Cities] =
    {
        "Gribble City",
        "Gribbletown",
        //"New Gribble",
        //"San Gribble",
        "Gribble Vista"
    };

    int maxtemps[Years][Cities] = {
        {96, 100, 87, 101, 105},
        {96, 98, 91, 107, 104},
        {97, 101, 93, 108, 107},
        {98, 103, 95, 109, 108}
    };

    cout << "Maximum tempertures for 2008 - 2011\n\n";
    for (int city = 0; city < Cities; ++city)
    {
        if (city > 2)
            cout << "error" << endl;
        else
            cout << cities[city] << ":\t";

        for (int year = 0; year < Years; year++)
            cout << maxtemps[year][city] << "\t";
        cout << endl;
    }

    system("pause");
    return 0;
}

通过调试可以看到，数组后面的字符串为0x0(NULL),cout 输出0x0后不再输出。你可以把cout << cities[city] << ":\t";--》printf("%s\t",cities[city]); 就可以看到效果了，实质上你的代码是执行了i>3的语句的，只是没输出