Burger Time? |
Many times the problem isn't to find a restaurant but a drugstore. After a big lunch with fast food it's normal that we need a drugstore because our stomach begins to feel pain.
Given the locations of the restaurants and drugstores on a highway, you want to determine the minimum distance between a restaurant and a drugstore.
The first line of each test case gives an integer L ( 1 L 2000000) indicating the length of the highway.
The second line of each test case contains a string S of length L, showing the positions of the restaurants and drugstores along the highway in the following manner:
You can suppose that every test case has at least one restaurant and at least one drugstore.
The end of the input is indicated when L = 0.
For each case in the input, print one line with the minimum distance between a restaurant and a drugstore.
2 RD 5 ..Z.. 10 .R......D. 10 .R..Z...D. 10 ...D..R... 25 ..D...R.RR...DD...D.R...R 0
1 0 7 0 3 2