【C语言】不使用循环和推断语句，求出1-100之间全部数的和

//不使用循环和推断语句，求出1-100之间全部数的和
#include <stdio.h>
int fun(int n, int *sum)
{
	*sum = *sum + n;
	(n--) && (fun(n, sum));
	return n;
}
int main()
{
	int n = 100;
	int sum = 0;
	fun(n, &sum);
	printf("%d\n", sum);
	return 0;
}
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