Added Merge sort in C

C/mergesort.c

@@ -0,0 +1,63 @@
+#include<stdio.h>
+ #include<stdlib.h>
+void mergesort(int a[],int i,int j);
+void merge(int a[],int i1,int j1,int i2,int j2);
+
+int main()
+{
+	int a[30],n,i;
+	printf("Enter no of elements:");
+	scanf("%d",&n);
+	printf("Enter array elements:");
+
+	for(i=0;i<n;i++)
+		scanf("%d",&a[i]);
+
+	mergesort(a,0,n-1);
+
+	printf("\nSorted array is :");
+	for(i=0;i<n;i++)
+		printf("%d ",a[i]);
+
+	return 0;
+}
+
+void mergesort(int a[],int i,int j)
+{
+	int mid;
+
+	if(i<j)
+	{
+		mid=(i+j)/2;
+		mergesort(a,i,mid);
+		mergesort(a,mid+1,j);
+		merge(a,i,mid,mid+1,j);
+	}
+}
+
+void merge(int a[],int i1,int j1,int i2,int j2)
+{
+	int temp[50];
+	int i,j,k;
+	i=i1;
+	j=i2;
+	k=0;
+
+	while(i<=j1 && j<=j2)
+	{
+		if(a[i]<a[j])
+			temp[k++]=a[i++];
+		else
+			temp[k++]=a[j++];
+	}
+
+	while(i<=j1)
+		temp[k++]=a[i++];
+
+	while(j<=j2)
+		temp[k++]=a[j++];
+
+
+	for(i=i1,j=0;i<=j2;i++,j++)
+		a[i]=temp[j];
+}