All Sorting Algos

Problems and General Algos/sorting_algos.cpp

@@ -0,0 +1,98 @@
+#include<iostream>
+using namespace std;
+
+void swap(int *x,int* y){
+    int temp;
+    temp=*x;
+    *x=*y;
+    *y=temp;
+}
+
+void insertion_sort(int a[],int n){
+    int i,j,x;
+    for(i=1;i<n;i++){
+        j=i-1;
+        x=a[i];
+        while(j>-1 && a[j]>x){
+            a[j+1]=a[j];
+            j--;
+        }
+        a[j+1] = x;
+
+    }   
+}
+
+void selection_sort(int a[],int n){
+    int i,j,k;
+    for(i=0;i<n-1;i++){
+        for(j=k=i;j<n;j++){
+            if(a[j] < a[k])
+                k=j;
+        }
+        swap(&a[i],&a[k]);
+    }
+}
+
+void merge(int a[],int l,int mid,int h){
+    int i=l,j=mid+1,k=l;
+    int b[100];
+
+    while(i<=mid && j<=h){
+        if(a[i]<a[j])
+            b[k++]=a[i++];
+        else
+            b[k++]=a[j++];
+
+    }
+
+    for(;i<=mid;i++)
+        b[k++]=a[i];
+    for(;j<=h;j++)
+        b[k++]=a[j];
+
+    for(int i=l;i<=h;i++)
+        a[i]=b[i];
+
+}
+
+void IMergesort(int a[],int n){
+    int p,i,l,h,mid;
+
+    for(p=2;p<=n;p=p*2){
+        for(i=0;i+p-1<n;i=i+p){
+            l=i;
+            h=i+p-1;
+            mid = (l+h)/2;
+            merge(a,l,mid,h);
+        }
+    }
+    if(p/2 < n)
+        merge(a,0,p/2-1,n-1);
+}
+
+void shellsort(int a[],int n){
+    int gap,i,j,temp;
+    for(gap=n/2;gap>=1;gap/=2){
+        for(i=gap;i<n;i++){
+            temp= a[i];
+            j= i-gap;
+            while(j>0 && a[j]>temp){
+                a[j+gap] = a[j];
+                j=j-gap;
+
+            }
+            a[j+gap] = temp;
+        }
+    }
+}
+int main(){
+    int a[] = {2,4,1,8,5,28,18,6};
+    int n= sizeof(a)/sizeof(a[0]);
+    int i;
+    // selection_sort(a,n);
+    // IMergesort(a,n);
+    shellsort(a,n);
+    for(i=1;i<n;i++)
+        cout<<" "<<a[i];
+    return 0;
+}