Codeforces Round #326 (Div. 2)Problem C - Duff and Weight Lifting

#include<cstdio>
int n,j,a[1000005],ans;
main()
{
	scanf("%d",&n);
	for(int i=0;i<n;i++)
	{
		scanf("%d",&q);
		a[j]++;
	}
	for(int i=0;i<1111110;i++)
	{
		if(a[i]%2==1) ans++;
		a[i+1]+=(a[i]/2);
	}
	printf("%d",ans);
}

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