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Coding Practice

Fix the function below so that it returns how many even numbers are in nums. Select the Parsonsprob tab for hints for the construction of the code.

#include <iostream> #include <vector> using namespace std; int evenCount (const vector<int> &vec) { for (size_t i = 0; i < vec.size(); i++) { if (i % 2 == 0) { count++; } } return count; } int main() { vector<int> vec{1,2,3,4}; cout << evenCount(vec) << endl; }

Fix the function below so that it returns how many even numbers are in nums. Use the lines to construct the code, then go back to complete the Activecode tab.

        int evenCount (const vector &vec) {
---
    int count = 0;
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    int count; #distractor
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    for (size_t i = 0; i < vec.size(); i++) {
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        if (vec[i] % 2 == 0) {
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        if (vec[i] % 2 != 0) { #paired
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            count++;
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        }
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    }
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    return count;
---
}
        

Someone could have COVID-19 if their temperature is above 99.9 degrees Fahrenheit. Finish the code below so that it counts and prints how many students in the class may have been exposed. Select the Parsonsprob tab for hints for the construction of the code.

#include <iostream> using namespace std; int main () { vector<double> temps = {98.6, 97.8, 100.3, 97.2, 98.7, 97.8, 99.8, 96.9, 98.2, 99.1, 99.9}; int covid_count = 0; for (size_t i = 0; i < temps.size(); i++) { } }

Someone could have COVID-19 if their temperature is above 99.9 degrees Fahrenheit. Finish the code below so that it counts and prints how many students in the class may have been exposed. Use the lines to construct the code, then go back to complete the Activecode tab.

        #include 
#include 
using namespace std;
---
int main() {
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    vector temps = {98.6, 97.8, 100.3, 97.2, 98.7, 97.8, 99.8, 96.9, 98.2, 99.1, 99.9};
---
    int covid_count = 0;
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    for (size_t i = 0; i < temps.size(); i++) {
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        if (temps[i] > 99.9) {
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            covid_count++;
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        }
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    }
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    cout << covid_count << endl;
---
}
        

Write the function endsEven that takes a vector and removes elements from the end of the vector until it ends with an even number. Select the Parsonsprob tab for hints for the construction of the code.

#include <iostream> #include <vector> using namespace std; // Write the endsEven function here int main() { vector<int> vec{1,2,3,4,5,6,7,7,9}; endsEven(vec); for(size_t i = 0; i < vec.size(); i++) { cout << vec[i] << endl; } }

Write the function endsEven that takes a vector and removes elements from the end of the vector until it ends with an even number. Use the lines to construct the code, then go back to complete the Activecode tab.

        void endsEven (vector &vec) {
---
vector endsEven (vector &vec) { #distractor
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    while (vec.back() % 2 != 0) {
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    for (size_t i = 0; i < vec.size(); i++) { #paired
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        vec.pop_back();
---
    }
---
}
        

Write the function randomNums that takes two integers: num which is the number of random numbers you wish to generate, and max, which is the maximum value of random number you wish to generate. Your function should return a vector of num integers that are between 1 and max, inclusive. Select the Parsonsprob tab for hints for the construction of the code.

#include <iostream> #include <cstdlib> #include <vector> using namespace std; // Write the randomNums function here int main() { int num = 10; int max = 100; randomNums(num,max); for (size_t i = 0; i < randomNums(num,max).size(); i++) { cout << randomNums(num,max)[i] << endl; } }

Write the function randomNums that takes two integers: num which is the number of random numbers you wish to generate, and max, which is the maximum value of random number you wish to generate. Your function should return a vector of num integers that are between 1 and max, inclusive. Use the lines to construct the code, then go back to complete the Activecode tab.

        vector randomNums (int num, int max) {
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    vector randomVec(num);
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    for (int i = 0; i < num; i++) {
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    for (int i = 0; i <= randomVec.size(); i++) { #paired
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        randomVec[i] = rand() % max + 1;
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    }
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    return randomVec;
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    return randomVec[i]; #distractor
---
}
        

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Write the function hundyBundy that returns a count of all numbers in the passed vector vec that are divisible by 100. Select the Parsonsprob tab for hints for the construction of the code.

#include <iostream> #include <vector> using namespace std; // Write the hundyBundy function here int main() { vector<int> vec{ 100,10,300,400,21,1000 }; cout << hundyBundy(vec) << endl; }

Write the function hundyBundy that returns a count of all numbers in the passed vector vec that are divisible by 100. Use the lines to construct the code, then go back to complete the Activecode tab.

        int hundyBundy (const vector vec) {
---
vector hundyBundy (const vector vec) { #paired
---
    int count = 0;
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    for (size_t i = 0; i < vec.size(); i++) {
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    for (size_t i = 0; i < count(); i++) { #distractor
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        if (vec[i] % 100 == 0) {
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            count++;
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        }
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    }
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    return count;
---
}
        

Write the function weird_print that prints the first half of a vector of integers in reverse order and then prints the second half in the order present in the vector. If we had vec = {1,2,3,4,5,6} we would print 3 2 1 4 5 6. You can assume the size of the vector will always be even. Select the Parsonsprob tab for hints for the construction of the code.

#include <iostream> #include <vector> using namespace std; // Write the weird_print function here int main() { vector<int> vec{1,2,3,4,5,6}; weird_print(vec); }

Write the function weird_print that prints the first half of a vector of integers in reverse order and then prints the second half in the order present in the vector. If we had vec = {1,2,3,4,5,6} we would print 3 2 1 4 5 6. You can assume the size of the vector will always be even. Use the lines to construct the code, then go back to complete the Activecode tab.

        void weird_print (vector vec) {
---
    size_t half = vec.size() / 2;
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    for (size_t i = vec.size() - 1; i >= half; i--){
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        cout << vec[i-half] << ' ';
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    }
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    for (size_t h = 0; h < half; h++) {
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        cout << vec[h + half] << ' ';
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    }
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    cout << endl;
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}
        

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