MergeSort.py

def merge_sort(arr):
    if len(arr)>1:
        left_arr=arr[:(len(arr)//2)]
        right_arr=arr[len(arr)//2:]
        
        merge_sort(left_arr)
        merge_sort(right_arr)
        
        i=0
        j=0
        k=0
        while(i<len(left_arr) and j<len(right_arr)):
            if(left_arr[i]<right_arr[j]):
                arr[k]=left_arr[i]
                i+=1
            else:
                arr[k]=right_arr[j]
                j+=1
            k+=1
        while(i<len(left_arr)):
            arr[k]=left_arr[i]
            i+=1
            k+=1
        while(j<len(right_arr)):
            arr[k]=right_arr[j];
            j+=1
            k+=1
            
            
array=[5,10,3,4,9,4,7]
merge_sort(array)
print(array)