Added uint editingDistance(const QString &s1, const QString &s2) for string comparision

[quassel.git] / src / common / util.cpp

diff --git a/src/common/util.cpp b/src/common/util.cpp
index 1c3d905..47541ee 100644 (file)
--- a/src/common/util.cpp
+++ b/src/common/util.cpp
@@ -97,3 +97,38 @@ bool readDataFromDevice(QIODevice *dev, quint32 &blockSize, QVariant &item) {
   in >> item;
   return true;
 }
+
+
+uint editingDistance(const QString &s1, const QString &s2) {
+  uint n = s1.size()+1;
+  uint m = s2.size()+1;
+  uint matrix[n][m];
+
+  for(uint i = 0; i < n; i++)
+    matrix[i][0] = i;
+
+  for(uint i = 0; i < m; i++)
+    matrix[0][i] = i;
+
+  uint min;
+  for(uint i = 1; i < n; i++) {
+    for(uint j = 1; j < m; j++) {
+      uint deleteChar = matrix[i-1][j] + 1;
+      uint insertChar = matrix[i][j-1] + 1;
+
+      if(deleteChar < insertChar)
+       min = deleteChar;
+      else
+       min = insertChar;
+      
+      if(s1[i-1] == s2[j-1]) {
+       uint inheritChar = matrix[i-1][j-1];
+       if(inheritChar < min)
+         min = inheritChar;
+      }
+
+      matrix[i][j] = min;
+    }
+  }
+  return matrix[n-1][m-1];
+}