HDU 1503 Advanced Fruits (LCS,变形)
题意:
给两个水果名,要求他们的LCS部分只输出1次,其他照常输出,但是必须保持原来的顺序!
思路:
求LCS是常规的,但是输出麻烦了,要先求LCS,再标记两串中的所有LCS字符,在遇到LCS字符时,先输串1的,再输串2的,然后输该字符,以保证每个LCS字符输出前,两串中该字符前面的字符全部已输出。
1 //#pragma comment(linker,"/STACK:102400000,102400000") 2 #include <iostream> 3 #include <stdio.h> 4 #include <string.h> 5 #include <vector> 6 #include <stack> 7 #include <algorithm> 8 #include <map> 9 #include <bits/stdc++.h> 10 #define LL long long 11 #define pii pair<int,int> 12 #define INF 0x7f7f7f7f 13 using namespace std; 14 const int N=100+5; 15 char s1[N], s2[N]; 16 17 int mark[N][N]; 18 int cnt[N][N]; 19 20 int pos1[N]; 21 int pos2[N]; 22 23 void LCS() 24 { 25 memset(mark, 0, sizeof(mark)); 26 memset(cnt, 0, sizeof(cnt)); 27 int len1=strlen(s1+1); 28 int len2=strlen(s2+1); 29 30 for(int i=1; i<=len1; i++) 31 { 32 for(int j=1; j<=len2; j++) 33 { 34 if(s1[i]==s2[j]) 35 { 36 cnt[i][j]=cnt[i-1][j-1]+1; 37 mark[i][j]=3; //斜的 38 } 39 else if(cnt[i-1][j]>=cnt[i][j-1]) 40 { 41 cnt[i][j]=cnt[i-1][j]; 42 mark[i][j]=2; //上边 43 } 44 else 45 { 46 cnt[i][j]=cnt[i][j-1]; 47 mark[i][j]=1; //左边 48 } 49 } 50 } 51 int t1=len1, t2=len2; 52 memset(pos1,0,sizeof(pos1)); 53 memset(pos2,0,sizeof(pos2)); 54 while(t1>0 && t2>0) 55 { 56 int pre=mark[t1][t2]; 57 58 if(pre==3) 59 { 60 pos1[t1]=1; 61 pos2[t2]=1; 62 t1--,t2--; 63 } 64 else if(pre==2) t1--; 65 else t2--; 66 } 67 int i=1, j=1; 68 69 while(1) 70 { 71 while(i<=len1 && !pos1[i]) 72 printf("%c",s1[i++]); 73 i++; 74 while(j<=len2 && !pos2[j]) 75 printf("%c",s2[j++]); 76 if(j<=len2) printf("%c",s2[j]); 77 j++; 78 if(i>len1&&j>len2) return ; 79 } 80 } 81 82 int main() 83 { 84 freopen("input.txt", "r", stdin); 85 while(~scanf("%s%s", s1+1, s2+1)) 86 { 87 LCS(); 88 printf("\n"); 89 } 90 return 0; 91 }