STL之string插入

  1 #include <iostream>
  2 #include <string>
  3
  4 using namespace std;
  5 int main()
  6 {
  7     string s("hello");
  8     string s2("abcdef");
  9
 10     string::iterator p = s.begin();
 11     cout << *p << endl;
 12     s.insert(p, ‘A‘);   //插入之后，p指向新插入的数据
 13     cout << *p << endl;
 14     cout << s << endl;
 15
 16     //每执行插入操作一次，gcc下必须重新给迭代器赋值
 17     //否则内存泄漏
 18     // 为什么呢？不明白
 19     p = s.begin();
 20     s.insert(p,‘B‘);
 21     cout << *p << endl;
 22     cout << s << endl;
 23
 24     string::iterator b = s2.begin();
 25     string::iterator e = s2.end();
 26
 27     p = s.begin();
 28     s.insert(p, b, e);
 29     cout << s << endl;
 30
 31     s = "hello";
 32     cout << s <<endl;
 33     s.assign(b, e);
 34     cout << s <<endl;
 35
 36     s.assign(8, ‘k‘);
 37     cout << s <<endl;
 38
 39     s = "abcdef";
 40     p = s.begin();
 41     s.erase(p);     //删除
 42     cout << s <<endl;
 43
 44     p = s.begin();
 45     p++;
 46     p++;
 47     string::iterator p2 = s.end();
 48     p2--;
 49     s.erase(p, p2);
 50     cout << s <<endl;
 51
 52     s = "hello";
 53     s2 = "abc";
 54     s.insert(0, 3, ‘A‘);
 55     cout << s <<endl;
 56
 57     s.insert(5, s2);    //位置从0开始，第6个元素之前
 58     cout << s <<endl;
 59
 60     s2 = "12345";
 61     s.insert(0, s2, 2, 3);
 62     cout << s <<endl;
 63
 64     char *cp = "Stately plump Buck";
 65     s.assign(cp, 7);
 66     cout << s <<endl;
 67     s.assign(cp);
 68     cout << s <<endl;
 69
 70     s = "hello";
 71     s.insert(0, cp, 7);
 72     cout << s <<endl;
 73     s = "hello";
 74     s.insert(0, cp);
 75     cout << s <<endl;
 76
 77     s = "hello";
 78     s2 = "abcdef";
 79     s.assign(s2, 2, 3);
 80     cout << s << endl;
 81
 82     s.erase(2, 3);
 83     cout << s <<endl;
 84
 85     s = "123456789";
 86     s.erase(s.size()-5, 1); //删除字符串的倒数第5个；
 87     cout << s <<endl;
 88
 89     s.insert(s.size(), 5, ‘!‘); //size()最后一个的后一个，insert在size（）之前插入；
 90     cout << s <<endl;
 91
 92     s = "abc";
 93     s.erase(0, 1).insert(0, "A");
 94     cout << s <<endl;
 95
 96     s = "abc";
 97     s[0] = ‘A‘;
 98     cout << s <<endl;
 99     return 0;
100 }
101