Time Limit: 3000MS | Memory Limit: Unknown | 64bit IO Format: %lld & %llu |
Description

Problem E
All in All
Input: standard input
Output: standard output
Time Limit: 2 seconds
Memory Limit: 32 MB
You have devised a new encryption technique which encodes a message by inserting between its characters randomly generated strings in a clever way. Because of pending patent issues we will not discuss in detail how the strings are generated and inserted into the original message. To validate your method, however, it is necessary to write a program that checks if the message is really encoded in the final string.
Given two strings s and t, you have to decide whether s is a subsequence of t, i.e. if you can remove characters from t such that the concatenation of the remaining characters is s.
Input Specification
The input contains several testcases. Each is specified by two strings s, t of alphanumeric ASCII characters separated by whitespace. Input is terminated by EOF.
Output Specification
For each test case output, if s is a subsequence of t.
Sample Input
sequence subsequence
person compression
VERDI vivaVittorioEmanueleReDiItalia
caseDoesMatter CaseDoesMatter
Sample Output
Yes
No
Yes
No
Source: ULM Local Contest
分析:
刘汝佳大白书里的水题。一开始居然把Yes和No写错了,结果错了几发,仔细看了一下,改了过来,就AC了。
uva又挂了,在poj1936交了一发(跟uva上的题一样,并且更详细,比如,规定:The length of s and t will no more than 100000.),ac了。
ac代码:(1)
#include <iostream> #include<cstdio> #include<algorithm> #include<cstring> using namespace std; const int maxn=100005; char s[maxn],t[maxn]; int main() { while(scanf("%s%s",s,t)!=EOF) { int n=strlen(s),m=strlen(t); /*if(n>m) { printf("No\n"); continue; }*/ int i; int j=0; for(i=0;i<n;i++) { for(;j<m;j++) { if(s[i]==t[j]) { j++;break; } } if(j==m) break; } if(i==n||i==n-1&&s[n-1]==t[m-1]) printf("Yes\n"); else printf("No\n"); } return 0; }
ac代码:(2)
#include <iostream> #include<cstdio> #include<algorithm> #include<cstring> using namespace std; const int maxn=100005; char s[maxn],t[maxn]; int main() { while(scanf("%s%s",s,t)!=EOF) { int n=strlen(s),m=strlen(t); if(n>m) { printf("No\n"); continue; } int i; int j=0; for(i=0;i<m;i++) { if(t[i]==s[j]&&j++==n-1) { break; } } if(j==n) printf("Yes\n"); else printf("No\n"); } return 0; }