POJ1131(AC).cpp

#define _CRT_SECURE_NO_WARNINGS
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;

const int MAXN = 2000;
int a[MAXN];
int b[MAXN];
char s[MAXN];
int f[10][4] = {
	{0, 0, 0, 0}, {0, 1, 2, 5}, {0, 2, 5, 0}, {0, 3, 7, 5}, {0, 5, 0, 0}, 
	{0, 6, 2, 5}, {0, 7, 5, 0}, {0, 8, 7, 5}, {1, 0, 0, 0}, {1, 1, 2, 5}
};

int main()
{
	int len, i, j;

	while(scanf("%s", s) == 1){
		memset(a, 0, MAXN * sizeof(int));
		memset(b, 0, MAXN * sizeof(int));
		if(s[0] == '1'){
			printf("%s [8] = 1 [10]\n", s);
			continue;
		}

		len = strlen(s);
		i = len - 1;
		j = 0;
		while(s[i] != '.'){
			memset(b, 0, MAXN * sizeof(int));
			for(j = 0; j < MAXN - 3; ++j){
				if(a[j] > 0){
					b[j] += f[a[j]][0];
					b[j + 1] += f[a[j]][1];
					b[j + 2] += f[a[j]][2];
					b[j + 3] += f[a[j]][3];
				}else{
					continue;
				}
			}
			b[0] += f[s[i] - '0'][1];
			b[1] += f[s[i] - '0'][2];
			b[2] += f[s[i] - '0'][3];
			for(j = MAXN - 1; j > 0; --j){
				b[j - 1] += b[j] / 10;
				b[j] %= 10;
			}
			b[0] %= 10;
			memcpy(a, b, MAXN * sizeof(int));
			--i;
		}

		printf("%s [8] = ", s);
		j = MAXN - 1;
		while(j >= 0 && a[j] == 0){
			--j;
		}
		if(j >= 0){
			printf("0.");
			for(i = 0; i <= j; ++i){
				printf("%d", a[i]);
			}
		}else{
			printf("0");
		}
		printf(" [10]\n");
	}

	return 0;
}