poj 1068 Parencodings
Parencodings
Time Limit: 1000MS | Memory Limit: 10000K | |
Total Submissions: 17066 | Accepted: 10221 |
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
//模拟题,先将右括号补齐 //用一个数组记录左括号为0,右括号为1 //然后扫一遍 #include<stdio.h> #include<string.h> int a[200000];//p序列 int b[200000];//整个括号用0与1表示 int c[200000];//w序列 int main() { int i,j,n,t,k,cnt,ans,p,flag; scanf("%d",&t); while(t--) { flag=0; scanf("%d",&n); for(i=1;i<=n;i++) scanf("%d",&a[i]); k=0; for(i=1;i<=n;i++) { for(j=0;j<a[i]-a[i-1];j++)//补齐左括号 { b[k++]=0; } b[k++]=1;//补齐右括号 } p=0; for(i=0;i<2*n;i++)//最多有2*n个括号 { cnt=1; ans=1; flag=0; if(b[i]==1) { k=i; flag=1; for(j=i-1;j>=0;j--)//从右往左扫 { if(b[j]==1) { ans++;//记录右括号的数目,也就是匹配好了的括号数 cnt++;//右括号加1 } else cnt--;//左括号减1 if(cnt==0)//cnt记录的是左右括号的数目,如果相抵消就跳出 break; } } if(flag) { c[p++]=ans; i=k;//i是不断往前走的 } } for(i=0;i<n;i++) printf("%d%c",c[i],i==n-1?'\n':' '); } return 0; }