add ch06

cpp_source/ch6.cpp → cpp_source/ch05/ch5.cpp

@@ -1,10 +1,10 @@
 //
-// Created by cer on 17-9-19.
-// chapter 06
+// Created by cer on 17-9-18.
+// chapter 5
 // 语句
-#include <iostream>
-#include <stdexcept>
 
+#include <iostream>
+#include <vector>
 using namespace std;
 
 int divide(int a, int b){
@@ -27,3 +27,5 @@ int main(){
     }
     return 0;
 }
+
+

cpp_source/ch06/Chapter6.h

@@ -0,0 +1,17 @@
+//
+// Created by cer on 19-1-20.
+//
+
+#ifndef CPP_PRIMER_PRACTICE_CHAPTER6_H
+#define CPP_PRIMER_PRACTICE_CHAPTER6_H
+
+int fact(int val);
+int func();
+
+template <typename T>
+T abs(T i)
+{
+    return i >= 0 ? i : -i;
+}
+
+#endif //CPP_PRIMER_PRACTICE_CHAPTER6_H

cpp_source/ch06/ch6.cpp

@@ -0,0 +1,47 @@
+//
+// Created by cer on 17-9-19.
+// chapter 06
+// 函数
+
+#include <iostream>
+#include <string>
+
+using namespace std
+
+int fact(int i)
+{
+    return i > 1 ? i * fact(i - 1) : 1;
+}
+
+void interactive_fact()
+{
+    string const prompt = "Enter a number within [1, 13) :\n";
+    string const out_of_range = "Out of range, please try again.\n";
+    for (int i; cout << prompt, cin >> i; )
+    {
+        if (i < 1 || i > 12)
+        {
+            cout << out_of_range;
+            continue;
+        }
+        cout << fact(i) << endl;
+    }
+}
+
+bool str_subrange(const string &str1, const string &str2){
+    if(str1.size()==str2.size())
+        return str1==str2;
+    string::size_type size={min(str1.size(),str2.size())};
+    string::size_type i=0;
+    while(i!=size){
+        if(str1[i]!=str2[i])
+        return ; //error! no return value!
+  }
+}
+
+int main()
+{
+//    interactive_fact();
+    str_subrange();
+    return 0;
+}

cpp_source/ch06/fact.cpp

@@ -0,0 +1,21 @@
+//
+// Created by cer on 19-1-20.
+//
+
+#include "Chapter6.h"
+#include <iostream>
+
+int fact(int val)
+{
+    if (val == 0 || val == 1) return 1;
+    else return val * fact(val-1);
+}
+
+int func()
+{
+    int n, ret = 1;
+    std::cout << "input a number: ";
+    std::cin >> n;
+    while (n > 1) ret *= n--;
+    return ret;
+}

cpp_source/ch06/factMain.cpp

@@ -0,0 +1,14 @@
+//
+// Created by cer on 19-1-20.
+//
+
+
+#include "Chapter6.h"
+#include <iostream>
+
+int main()
+{
+    std::cout << "5! is " << fact(5) << std::endl;
+    std::cout << func() << std::endl;
+    std::cout << abs(-9.78) << std::endl;
+}