Counting Sort C++

Data-Structure/C++/Counting_Sort.cpp

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+#include <iostream>
+#include <vector>
+using namespace std;
+int smallInt = -1e9;
+int largeInt = 1e9;
+// Counting Sort
+// Note: Range of the input array can't exceed max size that can be assigned to a vector in your system.
+
+// Time complexity: O(N+K)
+// Space Complexity: O(K)
+// Where N = Number of elements and K = Largest Element - Smallest Element
+
+int findMax(vector<int>&vec){
+    int currMax = smallInt;
+    for(int i = 0 ; i < vec.size() ; i++){
+        if(currMax < vec[i]){
+            currMax = vec[i];
+        }
+    }
+    return currMax;
+}
+
+int findMin(vector<int>&vec){
+    int currMin = largeInt;
+    for(int i = 0 ; i < vec.size() ; i++){
+        if(currMin > vec[i]){
+            currMin = vec[i];
+        }
+    }
+    return currMin;
+}
+
+void countSort(vector<int>&vec){
+    int maxElement = findMax(vec);
+    int minElement = findMin(vec);
+    int range = maxElement - minElement + 1;
+
+    vector<int>count(range,0);
+    vector<int>output(vec.size());
+    for(int i = 0; i < vec.size(); i++)
+        count[vec[i] - minElement]++;
+
+    for(int i = 1; i < count.size(); i++)
+        count[i] += count[i - 1];
+
+    for(int i = vec.size() - 1; i >= 0; i--) {
+        output[count[vec[i] - minElement] - 1] = vec[i];
+        count[vec[i] - minElement]--;
+    }
+
+    for(int i = 0; i < vec.size(); i++)
+    vec[i] = output[i];
+}
+int main(){
+    int n;
+    cout<<"Enter number of elements : ";
+    cin>>n;
+    cout<<"Enter elements : ";
+    vector<int>vec(n);
+
+    // Taking input
+    for(int i = 0 ; i < n ; i++){
+        cin>>vec[i];
+    }
+
+    // Calling the countSort function
+    countSort(vec);
+
+    // Printing the sorted vector
+    cout<<"Sorted : ";
+    for(int i = 0 ; i < n ; i++){
+        cout<<vec[i]<<" ";
+    }
+    return 0;
+}