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 }