I have a polygon layer it contain some overlap polygons.[![enter image description here][1]][1] 


  [1]: https://i.sstatic.net/JPykq.jpg

I want Holes instead of overlap polygons.

i tried some code 
                


                      ESRI.ArcGIS.ArcMapUI.IMxDocument mxd = ArcMap.Application.Document 
             as ESRI.ArcGIS.ArcMapUI.IMxDocument;
                if (mxd.SelectedItem is ESRI.ArcGIS.Carto.IFeatureLayer)
                {
                    ESRI.ArcGIS.Carto.IFeatureLayer flay = mxd.SelectedItem as ESRI.ArcGIS.Carto.IFeatureLayer;
                    ESRI.ArcGIS.Geodatabase.IFeatureClass fcls = flay.FeatureClass;
                    ESRI.ArcGIS.Geodatabase.ISpatialFilter spatialFilter = new ESRI.ArcGIS.Geodatabase.SpatialFilterClass();

                    spatialFilter.SpatialRel = ESRI.ArcGIS.Geodatabase.esriSpatialRelEnum.esriSpatialRelOverlaps;
                    ESRI.ArcGIS.Geodatabase.IFeatureCursor fcur = flay.Search(spatialFilter, true);
                    ESRI.ArcGIS.Geodatabase.IFeature fea = fcur.NextFeature();
                    while (fea!=null)
                    {
                        ESRI.ArcGIS.Geometry.IGeometry geo= fea.Shape;
                        ESRI.ArcGIS.Geometry.IGeometryCollection gcoll = geo as ESRI.ArcGIS.Geometry.IGeometryCollection;
                       
                        fea = fcur.NextFeature();
                    }



further no Idea. Please give me suggestions.

thanks.