UVA 12105 - Bigger is Better(DP+高精度)

#include <stdio.h>
#include <string.h>

const int N = 105;
const int M = 3005;
const int num[10] = {6, 2, 5, 5, 4, 5, 6, 3, 7, 6};
int n, m;
char dp[N][M][55], ans[55], tmp[55];

void init() {
	scanf("%d", &m);
	memset(dp, 0, sizeof(dp));
	memset(ans, 0, sizeof(ans));
	dp[0][0][0] = ‘0‘;
}

int numcmp(char *a, char *b) {
	int lena = strlen(a);
	int lenb = strlen(b);
	if (lena < lenb) return -1;
	if (lena > lenb) return 1;
	return strcmp(a, b);
}

void DP(char *a, char *b, int k) {
	memset(tmp, 0, sizeof(tmp));
	strcpy(tmp, b);
	int len = strlen(b);
	if (tmp[0] == ‘0‘)
		tmp[0] = ‘0‘ + k;
	else
		tmp[len] = ‘0‘ + k;
	if (numcmp(a, tmp) < 0)
		strcpy(a, tmp);
}

int main() {
	int cas = 0;
	while (~scanf("%d", &n) && n) {
		init();
		for (int i = 0; i <= n; i++) {
			for (int j = 0; j < m; j++) {
				if (strlen(dp[i][j]) == 0) continue;
				for (int k = 0; k < 10; k++) {
					if (i + num[k] > n) continue;
					DP(dp[i + num[k]][(j * 10 + k) % m], dp[i][j], k);
				}
			}
			if (i != 0 && numcmp(ans, dp[i][0]) < 0)
				strcpy(ans, dp[i][0]);
		}
		printf("Case %d: ", ++cas);
		if (ans[0] == 0) printf("-1\n");
		else printf("%s\n", ans);
	}
	return 0;
}