题目描述：（待编辑）
分析：（待编辑）
1 #include <cstdio>
2 #include <cstring>
3
4 const int MAXN = 12;
5
6 char num1[MAXN], num2[MAXN], sum[MAXN], str[100];
7 int len1, len2, len3;
8 int char_to_num[30];
9 int Flag;
10 bool visnum[30];
11 int visch[30];
12 int lenth;
13 bool vis[9876543];
14
15 void init()
16 {
17 memset(char_to_num, 0, sizeof(char_to_num) );
18 char_to_num[ 'I' - 'A' ] = 1;
19 char_to_num[ 'X' - 'A' ] = 10;
20 char_to_num[ 'C' - 'A' ] = 100;
21 char_to_num[ 'M' - 'A' ] = 1000;
22 char_to_num[ 'V' - 'A' ] = 5;
23 char_to_num[ 'L' - 'A' ] = 50;
24 char_to_num[ 'D' - 'A' ] = 500;
25 return;
26 }
27
28 void InputDeal()
29 {
30 int i = 0, j = 0;
31 while ( str[i] && str[i] != '+' )
32 num1[j++] = str[i++];
33 num1[j] = '\0';
34 len1 = j;
35
36 j = 0;
37 ++i;
38 while ( str[i] && str[i] != '=' )
39 num2[ j++ ] = str[ i++ ];
40 num2[j] = '\0';
41 len2 = j;
42
43 j = 0;
44 ++i;
45 while ( str[i] )
46 sum[j++] = str[i++];
47 sum[j] = '\0';
48 len3 = j;
49 /*
50 puts(num1);
51 puts(num2);
52 puts(sum);
53 */
54 return;
55 }
56
57 int GetNum( char *ss )
58 {
59 int len = strlen(ss);
60 int number = char_to_num[ ss[len - 1] - 'A' ];
61 for ( int i = len - 2; i >= 0; --i )
62 {
63 int next = char_to_num[ ss[i + 1] - 'A' ];
64 int cur = char_to_num[ ss[i] - 'A' ];
65 if ( cur < next ) number -= cur;
66 else number += cur;
67 }
68 return number;
69 }
70
71 bool checkRoma()
72 {
73 int n1 = GetNum( num1 );
74 int n2 = GetNum( num2 );
75 int Sum = GetNum( sum );
76 // printf("%d %d %d\n", n1, n2, Sum );
77 return ( ( n1 + n2 ) == Sum );
78 }
79
80 bool Judge()
81 {
82 if ( ( len3 > 1 && !visch[ sum[0] - 'A' ] )
83 || ( len1 > 1 && !visch[ num1[0] - 'A' ] )
84 || ( len2 > 1 && !visch[ num2[0] - 'A' ] ) ) return false;
85 int n1 = 0;
86 int n2 = 0;
87 int Sum = 0;
88
89 int i = 0;
90 while ( num1[i] ) n1 = n1 * 10 + visch[ num1[i++] - 'A'];
91 i = 0;
92 while ( num2[i] ) n2 = n2 * 10 + visch[ num2[i++] - 'A'];
93 i = 0;
94 while ( sum[i] ) Sum = Sum * 10 + visch[ sum[i++] - 'A'];
95
96 // if ( n1 + n2 == Sum )
97 // printf( "%d %d %d\n", n1, n2, Sum );
98
99 return n1 + n2 == Sum;
100 }
101
102 int GetNNN()
103 {
104 int nn = 0;
105 if ( visch['I' - 'A' ] >= 0 )
106 nn += visch['I' - 'A' ];
107 if ( visch['X' - 'A' ] >= 0 )
108 nn += visch['X' - 'A' ] * 10;
109 if ( visch['C' - 'A' ] >= 0 )
110 nn += visch['C' - 'A' ] * 100;
111 if ( visch['M' - 'A' ] >= 0 )
112 nn += visch['M' - 'A' ] * 1000;
113 if ( visch['V' - 'A' ] >= 0 )
114 nn += visch['V' - 'A' ] * 10000;
115 if ( visch['L' - 'A' ] >= 0 )
116 nn += visch['L' - 'A' ] * 100000;
117 if ( visch['D' - 'A' ] >= 0 )
118 nn += visch['D' - 'A' ] * 1000000;
119
120 return nn;
121 }
122
123 void DFS( int cur, char *ss )
124 {
125 if ( Flag >= 2 ) return;
126 if ( cur >= lenth )
127 {
128 int nnn = GetNNN();
129 // printf("%d\n", nnn);
130 if ( !vis[nnn] )
131 {
132 vis[nnn] = true;
133 if ( Judge() ) ++Flag;
134 }
135 return;
136 }
137
138 for ( int i = 0; i < 10; ++i )
139 if ( !visnum[i] )
140 {
141 visnum[i] = true;
142
143 if ( visch[ ss[cur] - 'A' ] == -1 )
144 {
145 visch[ ss[cur] - 'A' ] = i;
146 DFS( cur + 1, ss );
147 visch[ ss[cur] - 'A' ] = -1;
148 }
149 else DFS( cur + 1, ss );
150
151 visnum[i] = false;
152
153 }
154 return;
155 }
156
157 int main()
158 {
159 init();
160 // freopen( "s.out", "w", stdout );
161 while ( scanf( "%s", str ), str[0] != '#' )
162 {
163 memset( vis, false, sizeof(vis) );
164
165 InputDeal();
166 if ( checkRoma() ) printf("Correct ");
167 else printf("Incorrect ");
168
169 memset( visnum, false, sizeof(visnum) );
170 memset( visch, -1, sizeof(visch) );
171
172 Flag = 0;
173
174 strcpy( str, num1 );
175 strcat( str, num2 );
176 strcat( str, sum );
177
178 lenth = strlen(str);
179 DFS( 0, str );
180
181 switch(Flag)
182 {
183 case 0:
184 puts("impossible");
185 break;
186
187 case 1:
188 puts("valid");
189 break;
190
191 default:
192 puts("ambiguous");
193 }
194 }
195 return 0;
196 }