oc字典放入到数组里，根据字典里的属性排序（重点）

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {

@autoreleasepool {

NSDictionary *dic1=@{@"name":@"小阳",

@"class":@"IOS8",

@"age":@"20"

};

NSDictionary *dic2=@{@"name":@"小红",

@"class":@"IOS8",

@"age":@"67"

};

NSDictionary *dic3=@{@"name":@"小丽",

@"class":@"IOS6",

@"age":@"12"

};

NSDictionary *dic4=@{@"name":@"小杨",

@"class":@"IOS8",

@"age":@"33"

};

NSDictionary *dic5=@{@"name":@"李俊威",

@"class":@"IOS6",

@"age":@"23"

};

NSDictionary *dic6=@{@"name":@"赵玉鑫",

@"class":@"IOS8",

@"age":@"9"

};

NSDictionary *dic7=@{@"name":@"胡旭阳",

@"class":@"IOS6",

@"age":@"20"

};

NSArray *arr=[[NSArray alloc]initWithObjects:dic1,dic2,dic3,dic4,dic5,dic6,dic7,nil];

//1.将以上四个字典存入数组中,输出数据以班级:XXX,姓名:XXX,年龄:XX格式。

NSLog(@"操作前数据