我的程序没有返回月份的值

Question

我必须使用什么来将月份存储为变量？ 当我运行代码时，它说“警告字符常量对于它的类型来说太长了”。

我创建了一个程序来检查给定月份中有多少天，因此我从用户那里获取一个值并将其放入m。我也尝试将m 的值作为（字符），但它不起作用。我检查这个月是二月还是另一个月。如果是二月，则要求输入年份，y，如果不是二月，则在所有条件下匹配m的值，并输出月份，m。

#include<iostream>
    using namespace std;
    int main(){
    char m;
    int y;
    cout<<"Plase Enter The month:- ";
    cin>>m;
    if (m=='january'||m=='march'||m=='april'||m=='may'||m=='june'||m=='july'||m=='august'||m=='september'||m=='december'||m=='october'||m=='november'||m=='jan'||m=='mar'||m=='apr'||m=='may'||m=='jun'||m=='jul'||m=='aug'||m=='sep'||m=='dec'||m=='oct'||m=='nov'||m=='JANUARY'||m=='MARCH'||m=='APRIL'||m=='MAY'||m=='JUNE'||m=='JULY'||m=='AUGUST'||m=='SEPTEMBER'||m=='OCTOBER'||m=='NOVEMBER'||m=='DECEMBER')
    {
        if (m=='jan'||m=='january'||m=='JANUARY')
        {
            cout<<"There Are 31";
        }
        else if (m=='march'||m=='mar'||m=='MARCH')
        {
            cout<<"There Are 31";
        }
        else if (m=='apr'||m=='april'||m=='APRIL')
        {
            cout<<"There Are 30";
        }
        else if (m=='may'||m=='MAY')
        {
            cout<<"There Are 31";
        }
        else if (m=='june'||m=='jun'||m=='JUNE')
        {
            cout<<"There Are 30";
        }
        else if (m=='jul'||m=='july'||m=='JULY')
        {
            cout<<"There Are 31";
        }
        else if (m=='aug'||m=='august'||m=='AUGUST')
        {
            cout<<"There Are 31";
        }
        else if (m=='sep'||m=='september'||m=='SEPTEMBER')
        {
            cout<<"There Are 30";
        }
        else if (m=='oct'||m=='october'||m=='OCTOBER')
        {
            cout<<"There Are 31";
        }
        else if (m=='nov'||m=='november'||m=='NOVEMBER')
        {
            cout<<"There Are 30";
        }
        else if (m=='dec'||m=='december'||m=='december')
        {
            cout<<"There Are 31";
        }
    }
    else if(m=='feburary'||m=='feb'||m=='FEBURARY'){
        cout<<"You Entered ";
        cout<<m;
        cout<<" which have more days in Leap year's ";
        cout<<"So Please Enter The year:- ";
        
        cin>>y;
        if (y>=1752)
    {
        
    if ((y-1752)%4==0)
    {
        cout<<"There are 29 days";
    }
    else if((y-1752)%4!=0){
        cout<<"There is 28 days";
    }}
    else{
        cout<<"The First leap is started from 1752 so Please enter Number Greater than it";
    }
    
    }
   else cout<<"------------------Please Enter A valid Month or Check Your Spelling--------------------";
        return 0;
    }

Answer 1

试试这个：

#include<iostream>
#include <string>
using namespace std;

int main() {
    std::string m;
    int y;
    cout << "Plase Enter The month:- ";
    cin >> m;
    if (m == "january" || m == "march" || m == "april" || m == "may" || m == "june" || m == "july" || m == "august" || m == "september" || m == "december" || m == "october" || m == "november" || m == "jan" || m == "mar" || m == "apr" || m == "may" || m == "jun" || m == "jul" || m == "aug" || m == "sep" || m == "dec" || m == "oct" || m == "nov" || m == "JANUARY" || m == "MARCH" || m == "APRIL" || m == "MAY" || m == "JUNE" || m == "JULY" || m == "AUGUST" || m == "SEPTEMBER" || m == "OCTOBER" || m == "NOVEMBER" || m == "DECEMBER")
    {
        if (m == "jan" || m == "january" || m == "JANUARY")
        {
            cout << "There Are 31";
        }
        else if (m == "march" || m == "mar" || m == "MARCH")
        {
            cout << "There Are 31";
        }
        else if (m == "apr" || m == "april" || m == "APRIL")
        {
            cout << "There Are 30";
        }
        else if (m == "may" || m == "MAY")
        {
            cout << "There Are 31";
        }
        else if (m == "june" || m == "jun" || m == "JUNE")
        {
            cout << "There Are 30";
        }
        else if (m == "jul" || m == "july" || m == "JULY")
        {
            cout << "There Are 31";
        }
        else if (m == "aug" || m == "august" || m == "AUGUST")
        {
            cout << "There Are 31";
        }
        else if (m == "sep" || m == "september" || m == "SEPTEMBER")
        {
            cout << "There Are 30";
        }
        else if (m == "oct" || m == "october" || m == "OCTOBER")
        {
            cout << "There Are 31";
        }
        else if (m == "nov" || m == "november" || m == "NOVEMBER")
        {
            cout << "There Are 30";
        }
        else if (m == "dec" || m == "december" || m == "december")
        {
            cout << "There Are 31";
        }
    }
    else if (m == "feburary" || m == "feb" || m == "FEBURARY") {
        cout << "You Entered ";
        cout << m;
        cout << " which have more days in Leap year\"s ";
            cout << "So Please Enter The year:- ";

        cin >> y;
        if (y >= 1752)
        {

            if ((y - 1752) % 4 == 0)
            {
                cout << "There are 29 days";
            }
            else if ((y - 1752) % 4 != 0) {
                cout << "There is 28 days";
            }
        }
        else {
            cout << "The First leap is started from 1752 so Please enter Number Greater than it";
        }

    }
    else cout << "------------------Please Enter A valid Month or Check Your Spelling--------------------";
    return 0;
}

在c++中，单引号'只能用于字符，例如'e'，但不能用于字符串，例如'hello'。对于字符串，请使用双引号，例如 "。

如果您希望将输入与其他内容进行比较，您还应该使用std::strings。

Answer 2

1. 您将m 声明为字符并将其用作字符串。
2. 您使用'' 来表示字符串，但您应该使用""。

@@ -1,70 +1,35 @@
 #include<iostream>
+#include<string>
 
 using namespace std;
 
 int main()
 {
-    char m;
+    string m;
     int y;
     cout<<"Plase Enter The month:- ";
     cin>>m;
-    if (m=='january'||m=='march' ...
+    if (m=="january"||m=="march" ...
     {
-        if (m=='jan'||m=='january'||m=='JANUARY')
+        if (m=="jan"||m=="january"||m=="JANUARY")
         {
             cout<<"There Are 31";
         }

Answer 3

其实m是一个字符。一个字符的大小是 1 个字节。这意味着你可以分配char m = 'q'; 但你不能说char m = 'qq'; 这里你必须使用一个字符数组，即char m[] = "qq";