add abbrevation solution to dp

dynamic_programming/abbreviation.py

@@ -0,0 +1,29 @@
+"""
+https://www.hackerrank.com/challenges/abbr/problem
+You can perform the following operation on some string, :
+
+1. Capitalize zero or more of 's lowercase letters at some index i
+   (i.e., make them uppercase).
+2. Delete all of the remaining lowercase letters in .
+
+Example:
+a=daBcd and b="ABC"
+daBcd -> capitalize a and c(dABCd) -> remove d (ABC)
+"""
+def abbr(a, b):
+    n = len(a)
+    m = len(b)
+    dp = [[False for _ in range(m + 1)] for _ in range(n + 1)]
+    dp[0][0] = True
+    for i in range(n):
+        for j in range(m + 1):
+            if dp[i][j]:
+                if j < m and a[i].upper() == b[j]:
+                    dp[i + 1][j + 1] = True
+                if a[i].islower():
+                    dp[i + 1][j] = True
+    return dp[n][m]
+
+
+if __name__ == "__main__":
+    print abbr("daBcd", "ABC") # expect True