Initial commit

c++/Others/A function object that computes an integer sum..cpp

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+A function object that computes an integer sum.
+#include <iostream>
+#include <vector>
+#include <algorithm>
+#include <functional>
+using namespace std;
+
+class sum : unary_function<int, void> {
+public:
+  argument_type sum;
+
+  sum() { sum = 0; }
+
+  result_type operator()(argument_type i) {
+  sum += i;
+  }
+};
+
+int main()
+{
+  vector<int> v;
+
+  for(int i=1; i < 11; i++) v.push_back(i);
+
+  for(unsigned i=0; i < v.size(); ++i){
+    cout << v[i] << endl;
+  }
+  sum s;
+
+  s = for_each(v.begin(), v.end(), sum());
+  cout << "sum of v: " << s.sum << endl;
+
+  return 0;
+}