题意:给出一串括号字符,求最多的匹配个数。
代码:
#include <map> #include <set> #include <cmath> #include <queue> #include <stack> #include <cstdio> #include <vector> #include <iomanip> #include <cstdlib> #include <cstring> #include <iostream> #include <algorithm> #define ll long long #define mod 1000000007 #define mem(a) memset(a,0,sizeof(a)) using namespace std; const int maxn = 100 + 5 , inf = 0x3f3f3f3f ; char s[maxn]; int dp[maxn][maxn]; int main(){ while(~scanf("%s",s+1)&&strcmp(s+1,"end")!=0){ int len = strlen(s+1); mem(dp); for(int l=1;l<=len;l++){ for(int i=1;i<=len-l+1;i++){ int j = i+l-1; if(s[i]=='('&&s[j]==')'||s[i]=='['&&s[j]==']') dp[i][j]=dp[i+1][j-1]+2; for(int k=i;k<=j;k++){ dp[i][j]=max(dp[i][j],dp[i][k]+dp[k+1][j]); } } } printf("%d\n",dp[1][len]); } return 0; }