1050. String Subtraction

标签：c++   pat   

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.

strlen（）本身就是一个循环，所以不要在循环中使用，超时了

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define N 10001
int main ()
{
    char str1[N],str2[N];
    bool flag[92];
    memset(flag,0,sizeof(flag));
    gets(str1);
    gets(str2);
    int i,length;
    length=strlen(str2);
    for( i=0;i<length;i++)
    {
         flag[str2[i]-' ']=true;
         }
    length=strlen(str1);
    for( i=0;i<length;i++)
    {
         if( flag[str1[i]-' ']!=true) printf("%c",str1[i]);
         }
    printf("\n");
    system("pause");
    return 0;
    }

1050. String Subtraction

标签：c++   pat   

原文地址：http://blog.csdn.net/lchinam/article/details/44096633