标签：出现 get turn err include iat cout pause sum
1.头文件：#include<sstream>
2.stringstream是C++提供的串流（stream）物件，其中：
clear()重置流的标志状态；str()清空流的内存缓冲，重复使用内存消耗不再增加！
在使用stringstream时遇到的问题：
#include <cstdlib> #include <iostream> #include <sstream> using namespace std; int main(int argc, char * argv[]) { stringstream stream; int a,b; stream<<"80"; stream>>a; stream<<"90"; stream>>b; cout<<a<<endl; cout<<b<<endl; system("PAUSE "); return EXIT_SUCCESS; }
运行结果：
预期b为90，但是出现-858993460，这是由于stringstream重复使用时，没有清空导致的。
修改之后：
#include <cstdlib> #include <iostream> #include <sstream> using namespace std; int main(int argc, char * argv[]) { stringstream stream; int a,b; stream<<"80"; stream>>a; stream.clear(); stream<<"90"; stream>>b; cout<<a<<endl; cout<<b<<endl; system("PAUSE "); return EXIT_SUCCESS; }
运行结果：
但是clear()仅仅清空标志位，并没有释放内存。
#include <cstdlib> #include <iostream> #include <sstream> using namespace std; int main(int argc, char * argv[]) { stringstream stream; int a,b; stream<<"80"; stream>>a; stream.clear(); cout<<"Size of stream = "<<stream.str().length()<<endl; stream<<"90"; stream>>b; cout<<"Size of stream = "<<stream.str().length()<<endl; cout<<a<<endl; cout<<b<<endl; system("PAUSE "); return EXIT_SUCCESS; }
clear()之后，虽然结果正确了，但是stream占用的内存却没有释放！在实际的应用中，要是多次使用stringstream，每次都增加占用的内存。
可以利用stringstream.str("")来清空stringstream。
void str ( const string & s ); // copies the content of string s to the string object associated with the string stream buffer. The function effectivelly calls rdbuf()->str(). Notice that setting a new string does not clear the error flags currently set in the stream object unless the member function clear is explicitly called.
#include <cstdlib> #include <iostream> #include <sstream> using namespace std; int main(int argc, char * argv[]) { stringstream stream; int a,b; stream<<"80"; stream>>a; cout<<"Size of stream = "<<stream.str().length()<<endl; stream.clear(); stream.str(""); cout<<"Size of stream = "<<stream.str().length()<<endl; stream<<"90"; stream>>b; cout<<"Size of stream = "<<stream.str().length()<<endl; cout<<a<<endl; cout<<b<<endl; system("PAUSE "); return EXIT_SUCCESS; }
运行结果：
stringstream默认空格会直接分词！
題目：输入的第一行有一个数字 N 代表接下來有 N 行数字，每一行数字里有不固定个数的整数，打印每一行的总和。
输入：
3
1 2 3
20 17 23 54 77 60
111 222 333 444 555 666 777 888 999
输出：
6
251
4995
string s; stringstream ss; int n, i, sum, a; cin >> n; getline(cin, s); // 换行读取 for (i=0; i<n; i++) { getline(cin, s); ss.clear(); ss.str(s); sum=0; while (1) { ss >> a; if ( ss.fail() )
break; sum+=a; } cout << sum << endl; }
标签：出现 get turn err include iat cout pause sum
原文地址：https://www.cnblogs.com/hhhhan1025/p/11521273.html
