C++ 使用For循环显示1个结果

这是我的代码：

void IDsearch(vector<Weatherdata>temp)
{
    int userinput;
    cout << "Enter the ID of the Event and i will show you all other information: " << endl;
    cin >> userinput;
    for(unsigned int i = 0; i < temp.size();i++)
    {
        if(userinput == temp[i].eventID)
        {
            cout << "Location: " << temp[i].location << endl;
            cout << "Begin Date: " << temp[i].begindate << endl;
            cout << "Begin Time: " << temp[i].begintime << endl;
            cout << "Event Type: " << temp[i].type << endl;
            cout << "Death: " << temp[i].death << endl;
            cout << "Injury: " << temp[i].injury << endl;
            cout << "Property Damage: " << temp[i].damage << endl;
            cout << "Latitude: " << temp[i].beginlat << endl;
            cout << "Longitude: " << temp[i].beginlon << endl;
        }
    }
}

void IDsearch（vectortemp）
{
int用户输入；
cout用户输入；
对于（无符号整数i=0；icout您可以使用标志来记住是否找到了某些元素

void IDsearch(const vector<Weatherdata>&temp) // use reference for better performance
{
    int userinput;
    bool found = false;
    cout << "Enter the ID of the Event and i will show you all other information: " << endl;
    cin >> userinput;
    for(unsigned int i = 0; i < temp.size();i++)
    {
        if(userinput == temp[i].eventID)
        {
            cout << "Location: " << temp[i].location << endl;
            cout << "Begin Date: " << temp[i].begindate << endl;
            cout << "Begin Time: " << temp[i].begintime << endl;
            cout << "Event Type: " << temp[i].type << endl;
            cout << "Death: " << temp[i].death << endl;
            cout << "Injury: " << temp[i].injury << endl;
            cout << "Property Damage: " << temp[i].damage << endl;
            cout << "Latitude: " << temp[i].beginlat << endl;
            cout << "Longitude: " << temp[i].beginlon << endl;
            found = true;
        }
    }
    if(!found)
    {
        cout << "it doesnt match" << endl;
    }
}

void IDsearch（const vector&temp）//使用引用可获得更好的性能
{
int用户输入；
bool-found=false；
cout用户输入；
对于（无符号整数i=0；icout您可以使用标志来记住是否找到了某些元素

void IDsearch(const vector<Weatherdata>&temp) // use reference for better performance
{
    int userinput;
    bool found = false;
    cout << "Enter the ID of the Event and i will show you all other information: " << endl;
    cin >> userinput;
    for(unsigned int i = 0; i < temp.size();i++)
    {
        if(userinput == temp[i].eventID)
        {
            cout << "Location: " << temp[i].location << endl;
            cout << "Begin Date: " << temp[i].begindate << endl;
            cout << "Begin Time: " << temp[i].begintime << endl;
            cout << "Event Type: " << temp[i].type << endl;
            cout << "Death: " << temp[i].death << endl;
            cout << "Injury: " << temp[i].injury << endl;
            cout << "Property Damage: " << temp[i].damage << endl;
            cout << "Latitude: " << temp[i].beginlat << endl;
            cout << "Longitude: " << temp[i].beginlon << endl;
            found = true;
        }
    }
    if(!found)
    {
        cout << "it doesnt match" << endl;
    }
}

void IDsearch（const vector&temp）//使用引用可获得更好的性能
{
int用户输入；
bool-found=false；
cout用户输入；
对于（无符号整数i=0；i
int i;
for (i=0; i<N; i++)
   if (...) {
     ...
     break; // i does not reach N
   }

if (i == N) { // never entered ifs in the for loop

inti；
对于（i=0；i一个很好的模式，“过去的方式”这样做：

int i;
for (i=0; i<N; i++)
   if (...) {
     ...
     break; // i does not reach N
   }

if (i == N) { // never entered ifs in the for loop

inti；
for（i=0；i另一种方法，几乎相当于在for循环中使用break语句

只需在向量中循环，然后在向量外打印结果

unsigned int i = 0;
for(; i < temp.size() && userinput != temp[i].eventID; ++i);

if(i < temp.size() && userinput == temp[i].eventID)
{
    cout << "Location: " << temp[i].location << endl;
    cout << "Begin Date: " << temp[i].begindate << endl;
    ....
}
else
{
    cout << "it doesnt match" << endl;
}    

无符号整数i=0；
对于（；icout还有另一种方法，几乎相当于在for循环中使用break语句

只需在向量中循环，然后在向量外打印结果

unsigned int i = 0;
for(; i < temp.size() && userinput != temp[i].eventID; ++i);

if(i < temp.size() && userinput == temp[i].eventID)
{
    cout << "Location: " << temp[i].location << endl;
    cout << "Begin Date: " << temp[i].begindate << endl;
    ....
}
else
{
    cout << "it doesnt match" << endl;
}    

无符号整数i=0；
对于（；i您也可以从
if
返回
，而不是使用标志。@Bob\uuuuu…如果保证
temp
中没有两个元素具有相同的
eventID
。您也可以从
if
返回
，而不是使用标志。@Bob\uuu…如果保证
temp
中没有两个元素具有相同的
事件ID
。