231A. Team

231A. Team

231A. Team

• time limit per test2 seconds
• memory limit per test256 megabytes
• inputstandard input
• outputstandard output

One day three best friends Petya, Vasya and Tonya decided to form a team and take part in programming contests. Participants are usually offered several problems during programming contests. Long before the start the friends decided that they will implement a problem if at least two of them are sure about the solution. Otherwise, the friends won't write the problem's solution.

一天，三个最好的朋友佩蒂娅、瓦西亚和托尼娅决定组成一个团队，参加编程比赛。在编程竞赛中，参与者通常会遇到几个问题。早在开始之前，朋友们就决定，如果至少有两个人对解决方案有把握，他们就会实施一个问题。否则，朋友们就不会写出问题的解决方案。

This contest offers n problems to the participants. For each problem we know, which friend is sure about the solution. Help the friends find the number of problems for which they will write a solution.

这场比赛为参赛者提供了n道题。对于我们知道的每一个问题，哪位朋友对解决方案是确定的。帮助朋友找到他们将要编写解决方案的问题数量。

Input

The first input line contains a single integer n (1 ≤ n ≤ 1000) — the number of problems in the contest. Then n lines contain three integers each, each integer is either 0 or 1. If the first number in the line equals 1, then Petya is sure about the problem's solution, otherwise he isn't sure. The second number shows Vasya's view on the solution, the third number shows Tonya's view. The numbers on the lines are separated by spaces.

第一个输入行包含一个整数n（1） ≤ N ≤ 1000）-竞赛中的问题数量。n行每行包含三个整数，每个整数为0或1。如果行中的第一个数字等于1，那么Petya肯定问题的解决方案，否则他不确定。第二个数字显示Vasya对解决方案的看法，第三个数字显示Tonya的看法。行上的数字用空格隔开。

Output

Print a single integer — the number of problems the friends will implement on the contest.

打印一个整数——朋友们将在比赛中解决的问题数。

Examples

input1

3

1 1 0

1 1 1

1 0 0

output1

2

input2

2

1 0 0

0 1 1

output2

1

Note

In the first sample Petya and Vasya are sure that they know how to solve the first problem and all three of them know how to solve the second problem. That means that they will write solutions for these problems. Only Petya is sure about the solution for the third problem, but that isn't enough, so the friends won't take it.

在第一个样本中，Petya和Vasya确信他们知道如何解决第一个问题，并且他们三人都知道如何解决第二个问题。这意味着他们将为这些问题编写解决方案。只有佩蒂亚对第三个问题的解决方案有把握，但这还不够，所以朋友们不会接受。

In the second sample the friends will only implement the second problem, as Vasya and Tonya are sure about the solution.

在第二个示例中，朋友们只会实现第二个问题，因为Vasya和Tonya对解决方案很确定。

Solution

Petya、Vasya、Tonya的看法大于等于2即对在比赛中解决的问题数进行累加

Code

#include <iostream>
using namespace std;

//231A.Team
int main() {
    int n = 0;//n：竞赛中的问题数量
    cin >> n;
    int sum = 0;//sum：在比赛中解决的问题数
    for(int i = 0;i < n;i++){
        int p,v,t=0;//p、v、t：Petya、Vasya、Tonya的看法
        cin >> p >> v >> t;
        if(p + v + t >= 2){
            sum++;
        }
    }
    cout << sum << endl;
    return 0;
}