HDU 1080 Human Gene Functions
最长公共子序列的变形
题目大意：给出两个基因序列，求这两个序列的最大相似度。
题目中的表格给出了两两脱氧核苷酸的相似度。
状态转移方程为：
dp[i][j] = max(dp[i-1][j]+Similarity(s1[i], '-'),
dp[i][j-1]+Similarity(s2[j], '-'),
dp[i-1][j-1]+Similarity(s1[i], s2[j]));
注意边界的初始化。
1 //#define LOCAL 2 #include <iostream> 3 #include <cstdio> 4 #include <cstring> 5 #include <algorithm> 6 using namespace std; 7 8 char s1[105], s2[105]; 9 int dp[105][105]; 10 11 int table[5][5] = { 12 5, -1, -2, -1, -3, 13 -1, 5, -3, -2, -4, 14 -2, -3, 5, -2, -2, 15 -1, -2, -2, 5, -1, 16 -3, -4, -2, -1, 0 17 }; 18 19 int max(int a, int b, int c) 20 { 21 return max(max(a, b), c); 22 } 23 24 int f(char c) 25 { 26 if(c == 'A') return 0; 27 if(c == 'C') return 1; 28 if(c == 'G') return 2; 29 if(c == 'T') return 3; 30 if(c == '-') return 4; 31 } 32 33 int Similarity(char c1, char c2) 34 { return table[f(c1)][f(c2)]; } 35 36 int main(void) 37 { 38 #ifdef LOCAL 39 freopen("1080in.txt", "r", stdin); 40 #endif 41 42 int T; 43 scanf("%d", &T); 44 while(T--) 45 { 46 int len1, len2, i, j; 47 dp[0][0] = 0; 48 scanf("%d %s", &len1, s1+1); 49 scanf("%d %s", &len2, s2+1); 50 for(i = 1; i <= len1; ++i) 51 dp[i][0] = dp[i-1][0] + Similarity(s1[i], '-'); 52 for(i = 1; i <= len2; ++i) 53 dp[0][i] = dp[0][i-1] + Similarity(s2[i], '-'); 54 for(i = 1; i <= len1; ++i) 55 for(j = 1; j <= len2; ++j) 56 dp[i][j] = max(dp[i-1][j]+Similarity(s1[i], '-'), 57 dp[i][j-1]+Similarity(s2[j], '-'), 58 dp[i-1][j-1]+Similarity(s1[i], s2[j])); 59 60 printf("%d\n", dp[len1][len2]); 61 } 62 return 0; 63 }
