pku2573.cpp

这是ACM 方面的资料 是PKU的 北京大学的出来的

#include <stdio.h>
#include <stdlib.h>

int B[1001], W[5000];
int N;

int main()
{
	int i, ans, e, a, b, c, d, k;
	while (scanf("%d", &N) != -1)
	{
		for (i = 0; i < N; i++)
		{
			scanf("%d", B + i);
		}
		if (N == 1)
		{
			printf("%d\n%d\n", B[0], B[0]);
			continue;
		}
		a = B[0];
		b = B[1];
		for (e = N - 2, k = 0, ans = 0; e > 1; e -= 2)
		{
			c = B[e];
			d = B[e + 1];
			if (a + c > 2 * b)
			{
				W[k++] = a;
				W[k++] = b;
				W[k++] = a;
				W[k++] = c;
				W[k++] = d;
				W[k++] = b;
				ans += a + 2 * b + d;
			}
			else
			{
				W[k++] = a;
				W[k++] = c;
				W[k++] = a;
				W[k++] = a;
				W[k++] = d;
				W[k++] = a;
				ans += c + d + 2 * a;
			}
		}
		if (e == 1)
		{
			W[k++] = a;
			W[k++] = B[2];
			W[k++] = a;
			ans += a + B[2];
		}
		W[k++] = a;
		W[k++] = b;
		ans += b;
		printf("%d\n", ans);
		for (i = 0; i < k - 3; i += 3)
		{
			printf("%d %d\n%d\n", W[i], W[i + 1], W[i + 2]);
		}
		printf("%d %d\n", W[k - 2], W[k - 1]);
	}
	return 0;
}