poj1068
Parencodings
Time Limit: 1000MS | Memory Limit: 10000K | |
Total Submissions: 24641 | Accepted: 14491 |
Description
Let S = s1 s2...s2n be a well-formed string of parentheses. S can be encoded in two different ways:
q By an integer sequence P = p1 p2...pn where pi is the number of left parentheses before the ith right parenthesis in S (P-sequence).
q By an integer sequence W = w1 w2...wn where for each right parenthesis, say a in S, we associate an integer which is the number of right parentheses counting from the matched left parenthesis of a up to a. (W-sequence).
Following is an example of the above encodings:
Write a program to convert P-sequence of a well-formed string to the W-sequence of the same string.
q By an integer sequence P = p1 p2...pn where pi is the number of left parentheses before the ith right parenthesis in S (P-sequence).
q By an integer sequence W = w1 w2...wn where for each right parenthesis, say a in S, we associate an integer which is the number of right parentheses counting from the matched left parenthesis of a up to a. (W-sequence).
Following is an example of the above encodings:
S (((()()()))) P-sequence 4 5 6666 W-sequence 1 1 1456
Write a program to convert P-sequence of a well-formed string to the W-sequence of the same string.
Input
The first line of the input contains a single integer t (1 <= t <= 10), the number of test cases, followed by the input data for each test case. The first line of each test case is an integer n (1 <= n <= 20), and the second line
is the P-sequence of a well-formed string. It contains n positive integers, separated with blanks, representing the P-sequence.
Output
The output file consists of exactly t lines corresponding to test cases. For each test case, the output line should contain n integers describing the W-sequence of the string corresponding to its given P-sequence.
Sample Input
2 6 4 5 6 6 6 6 9 4 6 6 6 6 8 9 9 9
Sample Output
1 1 1 4 5 6 1 1 2 4 5 1 1 3 9
Source
个人感觉编程能力实在是弱。一题简单模拟都卡了好久,还要抄网上的程序。
题意如下,给定一个完整的括号序列(每个左括号都有一个右括号和它对应),输入n行,输入这个序列第i个右括号前总共有几个左括号,求每个对应左右括号里面的左右括号数(包括它本身)。
思路如下:既然输入的是每个右括号之前所有的左括号数,那么久每读入一个数据,记录下A(i)-A(i-1)个左括号,再记录一个右括号。输出时,用递归法,若该括号是左括号,证明其可以再次向右递归,沿途向右递归记录下内部的括号总数,知道遇到了它的“另一半”,则结束递归,记录当前值。
15773121
ksq2013 | 1068 | Accepted | 696K | 0MS | G++ | 871B | 2016-07-21 13:18:24 |
#include<vector> #include<cstdio> #include<iostream> using namespace std; int n,cnt,w[10000]; vector<bool>bin; void in() { pair<int,int>p; p.first=p.second=0; for(int i=0;i<n;i++){ scanf("%d",&p.second); for(int j=1;j<=p.second-p.first;j++)bin.push_back(1); bin.push_back(0); p.first=p.second; } } int solve(int &l) { int res=1; for(;;){ if(bin[l]){ l++; res+=solve(l); } else{ l++; w[cnt++]=res; return res; } } } void out() { printf("%d",w[0]); for(int i=1;i<n;i++) printf(" %d",w[i]); putchar('\n'); } int main() { int T,l; scanf("%d",&T); for(;T;T--){ l=cnt=0; bin.clear(); scanf("%d",&n); in(); solve(l); out(); } return 0; }