pku1894.cpp

这是ACM 方面的资料 是PKU的 北京大学的出来的

#include <stdio.h>
#include <string.h>
int val[100];
char s[101];
int B, L;
int mod[1000], modcnt;

int Mod()
{
	int ans, i;
	for (i = L - 1; i > 0; i--)
	{
		val[i - 1] += val[i] % B * 100000000;
		val[i] /= B;
	}
	ans = val[0] % B;
	val[0] /= B;
	return ans;
}

int Zero()
{
	int i;
	for (i = 0; i < L; i++)
	{
		if (val[i])
		{
			return 0;
		}
	}
	return 1;
}

int main()
{
	char t;
	int i, j, ls, e, cnt;
	scanf("%d %s", &B, s);
	ls = strlen(s);

	e = ls;
	j = 0;
	L = (ls + 7) / 8;
	for (; e > 0; e -= 8, j++)
	{
		val[j] = 0;
		for (i = 8; i > 0; i--)
		{
			if (e - i < 0)
			{
				continue;
			}
			val[j] = val[j] * 10;
			val[j] += (s[e - i] - '0');
		}
	}
	
	cnt = 0;
	while (!Zero())
	{
		mod[cnt++] = Mod();
	}

	for (i = 0; i < cnt - 1; i++)
	{
		if (mod[i] <= 0)
		{
			mod[i] += B;
			mod[i + 1]--;
		}
	}
	i = cnt - 1;
	while (mod[i] == 0)
	{
		i--;
	}
	for (; i >= 0; i--)
	{
		printf("%d", mod[i]);
	}
	printf("\n");
	return 0;
}