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删除所有偶数项,并打印出删除的项1. vector/queue 正确方法1:void erase(vector<int> &v) { for(vector<int>::iterator vi=v.begin();vi!=v.end();) { if(*vi % 2 == 0) { cout << "Erasing " << *vi << endl; vi = v.erase(vi); } else ++vi; } } 正确方法2:void erase2(vector<int> &v) { for(vector<int>::reverse_iterator ri=v.rbegin();ri!=v.rend();) { if(*ri % 2 == 0) { cout << "Erasing " << *ri << endl; v.erase((++ri).base()); //erase()函数期待的是正向iterator,故而这里要调 //用base()函数将逆向iterator转换为正向的 } else ++ri; } }
2.map/list正确方法void erase(map<int,int> &m) { for(map<int,int>::iterator mi=m.begin();mi!=m.end();) { if(mi->second % 2 == 0) { cout << "Erasing " << mi->second << endl; m.erase(mi++); } else ++mi; } }
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