#import <Foundation/Foundation.h>#import "Person.h"//1.输出I love iosvoid output() {    printf("I love ios\n");}//2.求两个数的最大 int maxValue(int x, int y) {     return x > y ? x : y;}int main(int argc, const char * argv[]) {    @autoreleasepool {      //方法一:直接打印        output();                int max = maxValue(2, 5);        printf("max = %d", max);           //方法二:定义指针变量        void (*p)() = NULL;        p  = output; //指针指向对应的函数;        p();        int (*p)(int, int) = NULL;        p = maxValue;        int max =  p(2, 5);        printf("max = %d", max);                //方法三:函数重命名(打印多个同类型,会比较方便)        typedef int (*PFUN)(int, int);  //将函数类型重命名为PFUN        PFUN p1 = NULL;        p1 = maxValue;        int max = p1(2, 5);        printf("max = %d", max);

 //第四种方法 --- block       int (^max)(int, int) = ^int(int a, int b) {            return a > b ? a : b;        };        //如何调用block块       int value = http://www.mamicode.com/max(4, 6);        printf("value = http://www.mamicode.com/%d", value);