Array:Find the largest element/value form a given array using function

Find the largest element/value form a given array using function

#include<stdio.h>
#define MAX 100

int getMaxvalue();
int size;

int main()
{

    int a[MAX],max,i;
    printf("Enter the size of the array: \n");
    scanf("%d",&size);
    printf("Enter %d elements of an array: \n", size);
    for(i=0;i<size;i++)
    scanf("%d",&a[i]);
    max=getMaxvalue(a);
    printf("Largest element of an array is: %d",max);
    return 0;
}

int getMaxvalue(int a[])
{

    int i=1,max;

    max=a[0];

    while(i < size)
        {
      if(max<a[i])
           max=a[i];
      i++;
    }

    return max;
}