关于商城红包获取

其实这是在最近做商城的购物车时想到的,当有红包的时候怎么获取红包的最大数额问题 于是才有这个东西出现

NSMutableArray *redBags =[NSMutableArray arrayWithArray:@[@5,@15,@30,@40,@40,@50]]; //[NSMutableArray arrayWithArray:@[@5,@15,@25,@30,@50]];//  当前的红包
    NSMutableArray *redBagsSelected = [NSMutableArray array];
    for(int i = 0 ;i < 91;i++)
    {
        [redBagsSelected addObject:@0];
    }
    int price = 90;
    char state[6][91];
    
    for(int i = 0; i < redBags.count; i++)
    {
        for(int j = price; j >= [redBags[i] intValue]; j--)
        {
            int index = j- [redBags[i] intValue];
            int tmp = [redBagsSelected[index] intValue]+ [redBags[i] intValue];
            if(tmp > [redBagsSelected[j] intValue])
            {
                redBagsSelected[j] = [NSNumber numberWithInt:tmp];
                state[i][j] = 1;
            }
        }
    }

    NSLog(@"给的数字为%d,最接近数字为%d",price,[redBagsSelected[price] intValue]);
    for(int i = 0;i<6;i++)
    {
        NSLog(@"i == %s",state[i]);
        for(int j = 0; j< 101;j++)
        {
            NSLog(@"j == %d",state[i][j]);
        }
    }
    
    int i = (int)redBags.count;
    int j = price;
    
     NSLog(@"组合数字为:");
    while(i-- >= 0)
    {
        if(state[i][j] == 1)
        {
            NSLog(@"%d ",[redBags[i] intValue]);
            j -= [redBags[i] intValue];
        }
    }

还有就是获得不同的红包组合