# go - Generating combinatorial string from map

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### go - Generating combinatorial string from map

I have a map as such:

``````// map[int]          position in string
// map[rune]bool     characters possible at said position
func generateString(in map[int]map[rune]bool) []string {
// example: {0: {'A':true, 'C': true}, 1: {'E': true}, 2: {'I': true, 'X': true}}
result := []string{"AEI", "AEX", "CEI", "CEX"} // should generate these
return result
}
``````

The difference with all possible permutations is that we are specifying which permutations are possible by index and I think that's the real head-breaker here. by (71.8m points)

First, we need to convert `map[int]map[rune]bool` to `[]map[rune]bool` since `map` iteration isn't guaranteed to be sorted by key's

After that, this is a recursive approach

``````var res []string

func dfs(curString string, index int, in []map[rune]bool) {
if index == len(in) {
res = append(res, curString)
return
}

for ch, is := range in[index] {
if !is { // I assume booleans can be false
return
}
dfs(curString+string(ch), index+1, in)
}
}
``````

and we can call it with `dfs("", 0, arr)` where `arr` is given `map` converted to `slice` and answer will be in `res` variable