Alex needs to rearrange a string based on a predetermined order. He has two strings, 'order' and 's'. The 'order' string contains unique characters that were previously sorted in a specific order. The task is to permute the characters in 's' so that they match the order specified in the 'order' string. In other words, if character 'x' appears before character 'y' in the 'order' string, then 'x' should appear before 'y' in the permuted string. Print the permutation of 's' that satisfies this condition. Note that any characters in 's' that are not present in the 'order' string should be sorted in alphabetical order (a to z).