順序有影響，如果交換兩個(gè)if{}，空字符串時(shí)也會(huì)打印三個(gè)cout。

代碼 執(zhí)行順序都是從上到下? 從左到右的順序執(zhí)行，在 java 中我知道 他有時(shí)候代碼執(zhí)行順序會(huì)受到影響 然而你如果按照題中要求進(jìn)行一步一步進(jìn)行代碼編寫(xiě) 也不是不可能。 但是有可能增加不必要的步驟

第二個(gè)判斷只會(huì)影響是否輸出"you?are?a?administrator." 和后面的無(wú)關(guān)

一般先判斷條件在執(zhí)行操作，這個(gè)屬性編程習(xí)慣吧。比如有些條件不滿足則操作不同

#include?<iostream>
#include<string>
using?namespace?std;
int?main()
{
????cout?<<?"pleas?enter?your?name"?<<?endl;
????string?s1;
????getline(cin,?s1);
????if?(s1.empty())
????{
????????cout?<<?"this?is?empty"?<<?endl;
????????return?0;
????}
????cout?<<?"hello?"?<<?s1?<<?endl;
????if?(s1?==?"imooc")
????{
????????cout?<<?"you?are?the?admin"?<<?endl;
????}
????cout?<<?"your?name?is?:?"?<<?s1.size()?<<?"?characters"?<<?endl;
????cout?<<?"the?first?character?of?you?name?is?:?"?<<?s1[0]?<<?endl;
????return?0;

}

#include?<stdlib.h>
#include?<iostream>
#include?<string>
using?namespace?std;

int?main(){
????string?name;
????cout<<?"Please?input?your?name:"?<<?endl;
????getline(cin,name);
????if?(name.empty()){
????????cout?<<"input?is?NULL."?<<?endl;
????????system("pause");
????????return?0;
????}

????if?(name?==?"imooc"){
????????cout?<<?"you?are?a?administrator."?<<?endl;
????}

????cout?<<?"hello?"?+?name?<<?endl;
????cout?<<?"the?length?of?your?name:"?<<?name.size()?<<endl;
????cout?<<?"the?first?letter?of?your?name:"?<<?name[0]?<<endl;
????system("pause");
????return?0;
}