PAT_A1050#String Subtraction

Source:

PAT A1050 String Subtraction (20 分)

Description:

Given two strings S​1​​ and S​2​​, S=S​1​​−S​2​​ is defined to be the remaining string after taking all the characters in S​2​​ from S​1​​. Your task is simply to calculate S​1​​−S​2​​ for any given strings. However, it might not be that simple to do it fast.

Input Specification:

Each input file contains one test case. Each case consists of two lines which gives S​1​​ and S​2​​, respectively. The string lengths of both strings are no more than 1. It is guaranteed that all the characters are visible ASCII codes and white space, and a new line character signals the end of a string.

Output Specification:

For each test case, print S​1​​−S​2​​ in one line.

Sample Input:

They are students.
aeiou

Sample Output:

Thy r stdnts.

Keys:

• 哈希映射

Code:

 /*
 Data: 2019-07-21 19:47:24
 Problem: PAT_A1050#String Subtraction
 AC: 08:34

 题目大意：
 给定字符串S和T，把T中的字符从S中删去
 */

 #include<cstdio>
 #include<string>
 #include<iostream>
 using namespace std;
 char mp[]={};

 int main()
 {
 #ifdef    ONLINE_JUDGE
 #else
     freopen("Test.txt", "r", stdin);
 #endif

     string s,t;
     getline(cin,s);
     getline(cin,t);
     for(int i=; i<t.size(); i++)
         mp[t[i]]=;
     for(int i=; i<s.size(); i++)
         if(mp[s[i]]==)
             printf("%c", s[i]);

     return ;
 }

Given two strings S​1​​ and S​2​​, S=S​1​​−S​2​​ is defined to be the remaining string after taking all the characters in S​2​​ from S​1​​. Your task is simply to calculate S​1​​−S​2​​ for any given strings. However, it might not be that simple to do it fast.

Input Specification:

Each input file contains one test case. Each case consists of two lines which gives S​1​​ and S​2​​, respectively. The string lengths of both strings are no more than 1. It is guaranteed that all the characters are visible ASCII codes and white space, and a new line character signals the end of a string.

Output Specification:

For each test case, print S​1​​−S​2​​ in one line.

Sample Input:

They are students.
aeiou

Sample Output:

Thy r stdnts.