LNK2019无法解析外部符号help！

修改如下，供参考：

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <windows.h>
void HideCursor() //隐藏光标 
{
    HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
    CONSOLE_CURSOR_INFO cci;
    GetConsoleCursorInfo(hOut, &cci);
    cci.bVisible = FALSE;
    SetConsoleCursorInfo(hOut, &cci);
}
void GotoXY(int x, int y)   //光标移动到x，y位置 
{
    COORD pos = { x,y };
    HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);// 获取标准输出设备句柄
    SetConsoleCursorPosition(hOut, pos); //两个参数分别是指定哪个窗体，具体位置
}
int main()
{
    int x1 = 10, y1 = 1, x2 = x1 + 26 + 2, y2 = y1 + 20; 
    int i;
    char c;
    system("mode con cols=50 lines=25");
    HideCursor();
    HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
    Rectangle((HDC)hOut, x1, y1, x2, y2);//DrawRectangle(x1, y1, x2, y2);
    GotoXY(x1 + 2, y2 - 1);
    printf("ABCDEFGHIJKLMNOPQRSTUVWXYZ"); 
    do{
        c = rand() % 26 + 'A';
        for (i = y1 + 1; i < y2 - 1; i = i + 1)
        {
            GotoXY(x1 + c - 'A' + 2, i);
            printf("%c", c);
            Sleep(100);
            GotoXY(x1 + c - 'A' + 2, i);
            printf(" ");
        }
        GotoXY(x1 + c - 'A' + 2, i);
        printf("=");
        Sleep(200);
        GotoXY(x1 + c - 'A' + 2, i);
        printf("%c", c);
    } while (kbhit() == 0);
    return 0;
}