Add files via upload

Author: MathProgrammer

Explanations/Explanations - 10/Swap Sort Explanation.txt

@@ -0,0 +1,59 @@
+In this problem your goal is to sort an array consisting of n integers in at most n swaps. 
+For the given array find the sequence of swaps that makes the array sorted in the non-descending order. Swaps are performed consecutively, one after another.
+
+Note that in this problem you do not have to minimize the number of swaps � your task is to find any sequence that is no longer than n.
+
+--------------------------------
+
+Didn't expect a O(n^2) solution to pass. Took a long time to write it because I suspected there was a better solution.
+
+Be greedy and perform selection sort. In each iteration place the i-th smallest element at the i-th endex.
+
+Maintain a vector of pairs to keep track of the indices of the swaps. Don't swap if the element is already at the right position.
+
+(Although swapping an element with itself in the same index is allowed in this problem)
+
+In other words, perform selection sort.
+
+-------------------------------------
+
+int main()
+{
+    typedef pair <int, int> pair_int;
+
+    int no_of_elements;
+    scanf("%d", &no_of_elements);
+
+    vector <int> element(no_of_elements);
+
+    for(int i = 0; i < no_of_elements; i++)
+        scanf("%d", &element[i]);
+
+    vector <pair_int> swaps;
+    //Selection Sort
+    for(int i = 0; i < no_of_elements; i++)
+    {
+        int min_i_index = i;
+        for(int j = i + 1; j < no_of_elements; j++)
+        {
+            if(element[j] < element[min_i_index])
+                min_i_index = j;
+        }
+
+        if(min_i_index != i)
+        {
+            swaps.push_back(make_pair(i, min_i_index));
+
+            swap(element[min_i_index], element[i]);
+        }
+    }
+
+    printf("%u\n", swaps.size());
+    for(unsigned int i = 0; i < swaps.size(); i++)
+    {
+        printf("%d %d\n", swaps[i].first, swaps[i].second);
+    }
+    return 0;
+}
+
+