以下是一个指针的具体实例，如何完成这个程序的要求呢？

参考答案如下：

#include <stdio.h>
#include <stdlib.h>
int main() {

//定义指针变量

int *pointer = NULL;

int one = 100;

pointer = &one;

printf("%d\n", *pointer);

float *pointer_2 = NULL;

float two = 200.0;

pointer_2 = &two;

printf("%.2f\n", *pointer_2);

double *pointer_3 = NULL;

double three = 300.0;

pointer_3 = &three;

printf("%.2lf\n", *pointer_3);

char *pointer_4 = NULL;

char four = 'n';

pointer_4 = &four;

printf("%c\n", *pointer_4);

return EXIT_SUCCESS;
}