Scaena Felix
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 101 Accepted Submission(s): 49
Problem Description
Given a parentheses sequence consist of ‘(‘ and ‘)‘, a modify can filp a parentheses, changing ‘(‘ to ‘)‘ or ‘)‘ to ‘(‘.
If we want every not empty <b>substring</b> of this parentheses sequence not to be "paren-matching", how many times at least to modify this parentheses sequence?
For example, "()","(())","()()" are "paren-matching" strings, but "((", ")(", "((()" are not.
Input
The first line of the input is a integer T, meaning that there are T test cases.
Every test cases contains a parentheses sequence S only consists of ‘(‘ and ‘)‘.
1≤|S|≤1,000.
Output
For every test case output the least number of modification.
Sample Input
3
()
((((
(())
Sample Output
1
0
2
题解:水题。。。。匹配括号的个数。。。
代码:
1 #include<stdio.h> 2 #include<stack> 3 using namespace std; 4 const int MAXN=1100; 5 char m[MAXN]; 6 int main(){ 7 int T; 8 scanf("%d",&T); 9 while(T--){ 10 stack<char>st; 11 scanf("%s",m); 12 int k=0; 13 for(int i=0;m[i];i++){ 14 if(m[i]==‘(‘)st.push(m[i]); 15 else if(!st.empty())st.pop(),k++; 16 } 17 printf("%d\n",k); 18 } 19 return 0; 20 }