不同的NSArray对象的组合
我想在不同的arrays
findelements
的组合。 假设我有三个NSArray
对象:
NSArray *set1 = [NSArray arrayWithObjects:@"A",@"B",@"C", nil]; NSArray *set2 = [NSArray arrayWithObjects:@"a",@"b", nil]; NSArray *set3 = [NSArray arrayWithObjects:@"1",nil];
现在所需的答案是下面的数组
NSArray *combinations = [{A},{B},{C},{a},{b},{1},{A,a},{A,b},{A,1},{B,a},{B,b},{B,1},{a,1},{b,1},{A,a,1},{A,b,1},{B,a,1},{B,b,1},{C,a,1},{C,b,1}];
编辑目前我已经做了下面的代码,我可以得到两个长度的组合。
NSArray *set1 = [NSArray arrayWithObjects:@"A",@"B",@"C", nil]; NSArray *set2 = [NSArray arrayWithObjects:@"a",@"b", nil]; NSArray *set3 = [NSArray arrayWithObjects:@"1",nil]; NSArray *allSets = [NSArray arrayWithObjects:set1,set2,set3,nil]; NSMutableArray *combinations = [NSMutableArray new]; for (int index = 0; index < allSets.count; index++) { [combinations addObject:[NSMutableArray array]]; } NSMutableArray *singleCombinations = combinations[0]; for (NSArray *set in allSets) { [singleCombinations addObjectsFromArray:set]; } for (int outerIndex = 0; outerIndex < allSets.count-1; outerIndex++) { NSArray *set = allSets[outerIndex]; for (id object1 in set) { for (int innerIndex = outerIndex+1; innerIndex<allSets.count; innerIndex++) { NSArray *nextSet = allSets[innerIndex]; for (id object2 in nextSet) { NSString *combi = [NSString stringWithFormat:@"%@%@",object1,object2]; NSLog(@"%@",combi); } } } }
任何帮助?
使用以下函数将a2
所有元素附加到a1
每个元素:
NSArray *combinations(NSArray *a1, NSArray *a2) { NSMutableArray *result = [NSMutableArray array]; for (NSArray *elem1 in a1) { [result addObject:elem1]; for (id elem2 in a2) { [result addObject:[elem1 arrayByAddingObject:elem2]]; } } return result; }
你可以通过从一个空数组开始迭代地获得结果,并将其与你的集合相结合:
NSArray *set1 = @[@"A", @"B", @"C"]; NSArray *set2 = @[@"a", @"b"]; NSArray *set3 = @[@"1"]; NSArray *result = @[@[]]; result = combinations(result, set1); result = combinations(result, set2); result = combinations(result, set3);
显示结果:
for (NSArray *item in result) { NSLog(@"{ %@ }", [item componentsJoinedByString:@", "]); }
产量
{} {1} { 一个 } {a,1} {b} {b,1} { 一个 } {A,1} {A,a} {A,a,1} {A,b} {A,b,1} {B} {B,1} {B,a} {B,a,1} {B,b} {B,b,1} { C } {C,1} {C,a} {C,a,1} {C,b} {C,b,1}
如果您的应用程序环境中有数据库,则可以创build临时表并在它们之间进行交叉连接以获得所需的组合。 干杯