@@ -47,29 +47,52 @@ void quickSort(point *vector, int leftIndex, int rightIndex){
4747 return ;
4848}
4949
50- void quickSortY (point * vector , int leftIndex , int rightIndex ){
51- if (leftIndex < rightIndex ){
52- float pivot = vector [(int )((rightIndex + leftIndex )/2 )].y ;
53- int left = leftIndex , right = rightIndex ;
50+ // Receives a vector and the position of two sorted subvectors inside it - merges both of them into a fully sorted one
51+ void mergeSubvectors (point * vector , int firstLeftIndex , int firstRightIndex , int secondLeftIndex , int secondRightIndex ){
52+ int vectorSize = (firstRightIndex - firstLeftIndex + 1 ) + (secondRightIndex - secondLeftIndex + 1 );
53+ 54+ point * tmp = (point * )malloc (vectorSize * sizeof (point )); // Temporary vector in which the interpolation will occur
55+ 56+ int i , j , k = 0 ; // Auxiliar variables that'll index the for-loops
57+ 58+ // Loops through both subvectors, merging them
59+ for (i = firstLeftIndex , j = secondLeftIndex ; k < vectorSize ; k ++ ){
60+ 61+ // If there are still elements in both subvector
62+ if (i <= firstRightIndex && j <= secondRightIndex ){
63+ // Compares them and copies the lowest one to tmp
64+ if (vector [i ].y < vector [j ].y ){ tmp [k ] = vector [i ++ ]; }
65+ else { tmp [k ] = vector [j ++ ]; }
66+ }
5467
55- while ( 1 ){
56- // Selects elements from the left that are >= to the pivot
57- while ( vector [ left ]. y < pivot ){ left ++ ; }
68+ // If not, copies the remaining element to tmp
69+ else if ( i <= firstRightIndex ){ tmp [ k ] = vector [ i ++ ]; }
70+ else if ( j <= secondRightIndex ){ tmp [ k ] = vector [ j ++ ] ; }
5871
59- // Selects elements from the right that are <= to the pivot
60- while (vector [right ].y > pivot ){ right -- ; }
72+ }
6173
62- // If the swapping the above selected elements is worth it, do it
63- if (left < right ){ swapElements (vector , left ++ , right -- ); } // And pass to the next element
74+ // Copies the sorted vector in tmp to the original one, replacing the subvectors
75+ for (i = firstLeftIndex , j = secondLeftIndex , k = 0 ; k < vectorSize ; k ++ ){
76+ if (i <= firstRightIndex ){ vector [i ++ ] = tmp [k ]; }
77+ else { vector [j ++ ] = tmp [k ]; }
6478
65- // If the swap is not worth it, the vector was successfully partitionted
66- else { break ; }
79+ }
6780
68- }
81+ free ( tmp ); tmp = NULL ;
6982
70- // Sorts the partitions
71- quickSort (vector , leftIndex , right );
72- quickSort (vector , right + 1 , rightIndex );
83+ return ;
84+ }
85+ 86+ // MERGE SORT
87+ void mergeSort (point * vector , int leftIndex , int rightIndex ){
88+ int vectorSize = rightIndex - leftIndex + 1 ;
89+ 90+ if (vectorSize > 1 ){
91+ int middleIndex = (rightIndex + leftIndex ) / 2 ;
92+ 93+ mergeSort (vector , leftIndex , middleIndex );
94+ mergeSort (vector , middleIndex + 1 , rightIndex );
95+ mergeSubvectors (vector , leftIndex , middleIndex , middleIndex + 1 , rightIndex );
7396 }
7497
7598 return ;
@@ -98,7 +121,8 @@ float auxGetLowestDist(point *points, int leftIndex, int rightIndex){
98121 }
99122 }
100123
101- quickSortY (strip , 0 , stripSize - 1 );
124+ // quickSortY(strip, 0, stripSize-1);
125+ mergeSort (strip , 0 , stripSize - 1 );
102126
103127 float div = (strip [0 ].x > points [leftIndex ].x && strip [stripSize - 1 ].x < points [rightIndex ].x )
104128 ? auxGetLowestDist (strip , 0 , stripSize - 1 )
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