diff --git a/Solver/main5.py b/Solver/main5.py
new file mode 100755
index 0000000..69710d3
--- /dev/null
+++ b/Solver/main5.py
@@ -0,0 +1,62 @@
+#!/usr/bin/python3
+# -*- coding: utf-8 -*-
+
+"""
+:mod: module
+:author: `Éric W`
+:date: 2016, october
+
+"""
+
+GRID='''
+   +-------+-------+-------+
+   | 9 . 6 | . 2 8 | . . 3 |
+   | . 4 . | 5 . . | . . 1 |
+   | . 8 . | 9 . . | . 4 . |
+   +-------+-------+-------+
+   | 6 . . | . . . | . 7 . |
+   | . . 8 | 2 . 6 | 9 . . |
+   | . 3 . | . . . | . . 5 |
+   +-------+-------+-------+
+   | . 5 . | . . 3 | . 6 . |
+   | 1 . . | . . 2 | . 8 . |
+   | 2 . . | 8 7 . | 5 . . |
+   +-------+-------+-------+
+'''
+
+def usage():
+    print('Usage: {:s} <grid> <pause>'.format(sys.argv[0]))
+    print('where\n\t<grid> is a 81 characters string describing a valid sudoku grid')
+    print('\t<pause> is the pause between two tentatives')
+    print('\nExample: with the grid')
+    print(GRID)
+    print('and a pause of 0.5 second')
+    print('$ {:s} 906028003040500001080900040600000070008206900030000005050003060100002080200870500 0.5'.format(sys.argv[0]))
+    exit(1)
+    
+if __name__ == '__main__':
+    import sys, time
+    import sudoku_grid, sudoku_solver
+
+
+    if len(sys.argv) != 3:
+        usage()
+    else:
+        strgrid = sys.argv[1]
+        try:
+            grid = sudoku_grid.SudokuGrid(strgrid)
+        except sudoku_grid.SudokuGridError:
+            print('grid description is not valid')
+            usage()
+        try:
+            pause = float(sys.argv[2])
+        except ValueError:
+            print('pause argument is not valid')
+            usage()
+        print('Sudoku to solve')
+        grid.pretty_print()
+        _ = input('Tapez entrée pour continuer')
+        sols = sudoku_solver.solve_one(grid, pause)
+        
+    exit(0)
+    
diff --git a/Solver/sudoku_solver.py b/Solver/sudoku_solver.py
index 90e9a05..b3fa0f3 100644
--- a/Solver/sudoku_solver.py
+++ b/Solver/sudoku_solver.py
@@ -152,6 +152,7 @@ def solve_one(grid, pause=0):
             res = solve_one(grid, pause)
             if not res is None:
                 return res
+            grid[i, j] = EMPTY_SYMBOL
         return res