关于sscanf的提问

ww4445 @ 2020-12-18 18:51:24

#include<iostream>
#include<string>
#include<cctype>
#include<vector>
#include<cstdio>
using namespace std;
int main()
{
    int i1,s2,s3;
    string str1,str2,str3,len,str0;
    char ch1;
    vector<string> ans;
    cin>>i1;
    for(int i=1;i<=i1;i++)
    {
        cin>>str1;
        if(isalpha(str1[0]))
        {
            ch1=str1[0];
            cin>>str2>>str3; 
        }
        else
    {
        str2=str1;
        cin>>str3;
    }
        sscanf(str2,"%d",&s2);
        sscanf(str3,"%d",&s3);
        if(ch1=='a')
            sprintf(str0,"%d+%d=%d",s2,s3,s2+s3);
        if(ch1=='b')
            sprintf(str0,"%d-%d=%d",s2,s3,s2-s3);
        if(ch1=='c')
            sprintf(str0,"%d*%d=%d",s2,s3,s2*s3);
        sprintf(len,"%d",strlen(str0));
        ans.push_back(str0);
        ans.push_back(len);
    }
    return 0;
}

by _caiji_ @ 2020-12-18 18:54:27

sscanf不认识c++的string，它只认识c的char[]

by Baiwhiter @ 2020-12-18 19:28:58

• 仅提供思路，稍微帮你调了一下，代码仍不能够ac
• vector数组是多余的，我个人认为可以去除

  #include<iostream>
  #include<string>
  #include<cctype>
  #include<vector>
  #include<cstdio>
  #include<cstring>
  using namespace std;
  int main()
  {
  int i1,s2,s3;
  //string str1,str2,str3,len,str0;
  char str1[10010],str2[10010],str3[10010],len[10010],str0[10010];//换成char类型 
  char ch1;
  //vector<string> ans;
  cin>>i1;
  for(int i=1;i<=i1;i++)
  {
      cin>>str1;
      if(isalpha(str1[0]))
      {
          ch1=str1[0];
          cin>>str2>>str3; 
      }
      else
      {
         strncpy(str2,str1,strlen(str1));
         cin>>str3;
      }
      sscanf(str2,"%d",&s2);
      sscanf(str3,"%d",&s3);
      if(ch1=='a')
          sprintf(str0,"%d+%d=%d",s2,s3,s2+s3);
      if(ch1=='b')
          sprintf(str0,"%d-%d=%d",s2,s3,s2-s3);
      if(ch1=='c')
          sprintf(str0,"%d*%d=%d",s2,s3,s2*s3);
      sprintf(len,"%d",strlen(str0));
      cout<<str0<<endl;
      cout<<len<<endl;
      //string x,y;
      //x=str0,y=len;
      //ans.push_back(x);
      //ans.push_back(y);
  }
  return 0;
  }

by ww4445 @ 2020-12-18 19:56:38

@caijianhong 啊！谢谢，终于解决了！反反复复改了好久，没想到问题出在这

by ww4445 @ 2020-12-18 20:01:03

@Baiwhiter 谢谢！已经解决了，使用vector是想要练习一下，但是输入一行后直接输出该行结果而不是统一输出，不会影响吗？

by Baiwhiter @ 2020-12-18 20:05:02

@ww4445 不会的QuQ