ZOJ1004 Anagrams by Stack

地址： http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=1004

这题我的想法有点不太一样，如果直接用传说中的回溯，入栈出栈应该代码会很短，但是我用的思路比较不太一样。

我先从源字符串的最后开始 找 目标字符串的 第一位，然后利用找到字符在源字符串的当前位置和之前已有的 "i" 个数来确定 这次i的个数 和 这次结果是否合理。

找到第一个后，递归找第二个。具体的思路可以看代码。

代码比较长，思路也比较烦，之后会去网上看些别人的思路。

zoj1004_m1 
  1 /************************************************************************
  2  Function:        ZOJ1004: http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=1004
  3  History :        Create:2012年11月22日23:03:01 (Actually, it is, strictly, a completion time
  4  Owner:            Yang HaiTao( Dennis Young)
  5  Reflection:    There is a much easier way to make it(_2) using 回溯.
  6                 Maybe I don
  7 ************************************************************************/
  8 #include <stdio.h>
  9 #include <string.h>
 10 #include <math.h>
 11 
 12 /*Bound*/
 13 #define kIOArraySize        51
 14 #define kWordsArraySize    50
 15 /*    state    */
 16 #define kStateCheckTrue        1
 17 #define kStateCheckFalse        0
 18 #define kStateNotFound        0
 19 #define kStateHasFound        1
 20 
 21 int searchTarstrFromSrcstr(char *srcStr, char *tarStr, int inOutSum);
 22 void outputTLArray(int TLArray[kIOArraySize]);
 23 void resetTLArray(int TLArray[kIOArraySize]);
 24 void resetTLArrayByStep(int TLArray[kIOArraySize]);
 25 
 26 /************************************************************************
 27 *                        Global Variable                                    *                                                         
 28 ************************************************************************/
 29 /* 0: exit    1: in        2: out
 30 index0: currentIndex         1-1000->in,out to print.
 31 */
 32 int printTempLineArray[kIOArraySize] = {0};
 33 char charTable[3] = {'p', 'i', 'o'};
 34 
 35 int main()
 36 {
 37     char sourceWords[kWordsArraySize], targetWords[kWordsArraySize];
 38     int state;
 39 
 40     while (gets(sourceWords) != NULL && gets(targetWords) != NULL)
 41     {
 42         printf("[\n");
 43         state = searchTarstrFromSrcstr(sourceWords, targetWords, 0);
 44         printf("]\n");
 45     }
 46 
 47     return 0;
 48 }
 49 
 50 int searchTarstrFromSrcstr(char *srcStr, char *tarStr, int inOutSum)
 51 {
 52     int srcStrLength = 0;
 53     int tarStrLength = 0;
 54     int foundFlag = kStateNotFound;
 55     int i = 0;
 56     int k = 0;
 57     int howToNameThisNum = 0;
 58     char newSrcStr[kWordsArraySize] = {0};
 59 
 60     srcStrLength = strlen(srcStr);
 61     tarStrLength = strlen(tarStr);
 62 
 63     /*    error return and end return*/
 64     /* End of the String*/
 65     if (0 == srcStrLength && 0 == tarStrLength)
 66     {
 67         outputTLArray(printTempLineArray);
 68         return kStateCheckTrue;
 69     }
 70     else if (srcStrLength != tarStrLength)
 71     {
 72         /* it can not do this with different string length*/
 73         resetTLArray(printTempLineArray);
 74         return kStateCheckFalse;
 75     }
 76 
 77     /*search the 1st char of target string from last char of the source string*/
 78     for (i=srcStrLength - 1; i>=0; i--)
 79     {
 80         if (srcStr[i] == tarStr[0])
 81         {
 82             foundFlag = kStateHasFound;
 83 
 84             /* howToNameThisNum is a temp number which is important to the next step*/
 85             howToNameThisNum = i + 1 - inOutSum;
 86             if (howToNameThisNum < 0)
 87             {
 88                 /*NOTE:  <0 means, you need to out more than one char to get the char that you want,
 89                     but the unnecessary char will make your target word Wrong.*/
 90                 /* !!!!Important one!!!!!   you need to reset last step when the function will return false*/
 91                 resetTLArrayByStep(printTempLineArray);
 92                 return kStateCheckFalse;
 93             }
 94             else
 95             {
 96                 /*insert "i" into the print Array*/
 97                 for (k = 1; k<= howToNameThisNum; k++)
 98                 {
 99                     printTempLineArray[(printTempLineArray[0]+k)] = 1;
100                 }
101                 /*inset "o" into the print Array*/
102                 printTempLineArray[0] = 
103                     printTempLineArray[0] + howToNameThisNum+ 1;
104                 /*set the first flag number*/
105                 printTempLineArray[printTempLineArray[0]] = 2;
106                 
107                 /*creat new source string
108                 The way like this:            source:aabcd    target:b
109                     1.new=""    ->    2.new="aa"    ->     3.new="aacd"    */
110                 strcpy(newSrcStr,"");
111                 strncpy(newSrcStr, srcStr, i+1-1);
112                 newSrcStr[i] = '\0';
113                 strcat(newSrcStr, srcStr+i+1);
114 
115                 /*find the next char of the target string from the new source string*/
116                 if (kStateCheckFalse == searchTarstrFromSrcstr
117                     (newSrcStr, tarStr+1, inOutSum + howToNameThisNum - 1))
118                 {
119                     /*resetTLArray(printTempLineArray);
120                     //这里不用resetTLArray只需设置notfound*/
121                     /* you need set the foundFlag back to NotFound, begin the child function return false.*/
122                     foundFlag = kStateNotFound;
123                 }
124                 else
125                 {
126                     /*    This is IMPORTENT!!!!!!!*/
127                     resetTLArrayByStep(printTempLineArray);
128                 }
129             }
130         }
131     }
132 
133     if (kStateNotFound == foundFlag)
134     {
135         resetTLArray(printTempLineArray);
136         return kStateCheckFalse;
137     }
138     else
139         return kStateCheckTrue;
140 }
141 
142 void outputTLArray(int TLArray[kIOArraySize])
143 {
144     int i = 0;
145 
146     for (i = 1; i <= TLArray[0]; i++)
147     {
148         printf("%c ",charTable[TLArray[i]]);
149     }
150     printf("\n");
151 }
152 
153 void resetTLArray(int TLArray[kIOArraySize])
154 {
155     int i = 0;
156     for (i = 1; i <= TLArray[0]; i++)
157     {
158         TLArray[i] = 0;
159     }
160     TLArray[0] = 0;
161 }
162 
163 void resetTLArrayByStep(int TLArray[kIOArraySize])
164 {
165     int i = 0;
166     i = TLArray[0];
167     do 
168     {
169         TLArray[i] = 0;
170         i--;
171         TLArray[0]--;
172     } while(i>0 && TLArray[i] != 2);
173 }