PAT (Advanced Level) Practise 1050 String Subtraction (20)

1050. String Subtraction (20)

时间限制

100 ms

内存限制

65536 kB

代码长度限制

16000 B

判题程序

Standard

作者

CHEN, Yue

Given two strings S₁ and S₂, S = S₁ - S₂ is defined to be the remaining string after taking all the characters in S₂ from S₁. Your task is simply to calculate S₁ - S₂ 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 S₁ and S₂, respectively. The string lengths of both strings are no more than 10⁴. 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 S₁ - S₂ in one line.

Sample Input:

They are students.aeiou

Sample Output:

Thy r stdnts.

题意：给你两个字符串，第一个字符串中删除第二个字符串出现的所有字符

解题思路：把第二个字符串出现的字符进行标记即可

#include <iostream>  #include <cstdio>  #include <cmath>  #include <cstring>  #include <algorithm>  #include <stack>  #include <queue>  #include <vector>  #include <map>    using namespace std;    char s1[10009],s2[10009];int visit[10009];  int main()  {      gets(s1);    gets(s2);    for(int i=0;s2[i];i++)        visit[s2[i]]=1;    for(int i=0;s1[i];i++)        if(!visit[s1[i]])            printf("%c",s1[i]);    return 0;  }