NSArray作业1：放四个十进制三位数到一个数组中，然后按从小到大排序后组成一个新的数组

 1 #import <Foundation/Foundation.h>
 2 
 3 int main(int argc, const char * argv[]) {
 4     @autoreleasepool {
 5         int a=345,b=789,c=123,d=567;
 6         NSLog(@"a=%d,b=%d,c=%d,d=%d",a,b,c,d);
 7         NSNumber *numA=[[NSNumber alloc]initWithInt:a];
 8         NSNumber *numB=[[NSNumber alloc]initWithInt:b];
 9         NSNumber *numC=[[NSNumber alloc]initWithInt:c];
10         NSNumber *numD=[[NSNumber alloc]initWithInt:d];
11         NSArray *array1=[NSArray arrayWithObjects:numA,numB,numC,numD,nil];
12         NSArray *array2=[array1 sortedArrayUsingSelector:@selector(compare:)];
13         for(NSArray *array3 in array2){
14             NSLog(@"%@",array3);
15         }
16     }
17     return 0;
18 }