#include <stdio.h>
int main() {
int test,i = 0,a = NULL;
int max2 = 0;
int n;
int max = -1000000, min = 1000000;
while (scanf("%d", &n) == 1 && max2 < 50)
{
if(n < min) { min = n; }
if(n > max) { max = n; }
max2++;
}
printf("%d",min+max);
return 0;
}
Input should be like this "1 5 8 9 10", I don't know how many numbers would be entered so I have to use the while loop.
Try using do while to put the scanf inside the loop.
#include <stdio.h>
int main() {
int test,i = 0,a = NULL;
int max2 = 0;
int n;
int max = -1000000, min = 1000000;
do{
scanf("%d", &n);
if(n < min) { min = n; }
if(n > max) { max = n; }
max2++;
}while ( n == 1 && max2 < 50)
printf("%d",min+max);
return 0;
}
Related
I have implemented Merge & Quick Sort in the textbook what I've learned, and it says Time Complexities of each sorts are like this:
Merge Sort: O(n.log(n)) / Quick Sort: average O(n.log(n)) and O(n2) in the worst case (if key array is sorted).
So I executed the programs with Two types of Arrays: sorted and random, with different sizes.
Since I wanted to get the Average time, I have tried 10 times per each case.
Here is the code of Merge & Quick Sort:
#include <iostream>
#include <ctime>
#include <vector>
#include <algorithm>
using namespace std;
void Merge(vector<int>& s, int low, int mid, int high) {
int i = low;
int j = mid + 1;
int k = low;
vector<int> u(s);
while (i <= mid && j <= high) {
if (s.at(i) < s.at(j)) {
u.at(k) = s.at(i);
i++;
} else {
u.at(k) = s.at(j);
j++;
}
k++;
}
if (i > mid) {
for (int a = j; a < high + 1; a++) {
u.at(k) = s.at(a);
k++;
}
} else {
for (int a = i; a < mid + 1; a++) {
u.at(k) = s.at(a);
k++;
}
}
for (int a = low; a < high + 1; a++)
s.at(a) = u.at(a);
}
void MergeSort(vector<int>& s, int low, int high) {
int mid;
if (low < high) {
mid = (low + high) / 2;
MergeSort(s, low, mid);
MergeSort(s, mid + 1, high);
Merge(s, low, mid, high);
}
}
void swap(int& a, int& b) {
int tmp = a;
a = b;
b = tmp;
}
void Partition(vector<int>& s, int low, int high, int& pvpoint) {
int j;
int pvitem;
pvitem = s.at(low);
j = low;
for (int i = low + 1; i <= high; i++) {
if (s.at(i) < pvitem) {
j++;
swap(s.at(i), s.at(j));
}
pvpoint = j;
swap(s.at(low), s.at(pvpoint));
}
}
void QuickSort(vector<int>& s, int low, int high) {
int pvpoint;
if (high > low) {
Partition(s, low, high, pvpoint);
QuickSort(s, low, pvpoint - 1);
QuickSort(s, pvpoint + 1, high);
}
}
And each of these main() functions are printing the execution times in SORTED, and RANDOM key arrays.
you can see the result with adding one of these main functions in Visual Studio(C++):
//Sorted key array
int main() {
int s;
for (int i = 1; i < 21; i++) { //Size is from 300 to 6000
s = i * 300;
vector<int> Arr(s);
cout << "N : " << s << "\n";
//Assign Random numbers to each elements
Arr.front() = rand() % Arr.size();
for (int j = 1; j < Arr.size(); j++) { Arr.at(j) = ((737 * Arr.at(j - 1) + 149) % (Arr.size() * 5)); }
sort(Arr.begin(), Arr.end());
//QuickSort(Arr, 0, Arr.size() - 1); <- you can switch using this instead of MergeSort(...) below
for (int i = 0; i < 10; i++) { //print 10 times of execution time
clock_t start, end;
start = clock();
MergeSort(Arr, 0, Arr.size() - 1);
end = clock() - start;
printf("%12.3f ", (double)end * 1000.0 / CLOCKS_PER_SEC);
}
cout << endl;
}
return 0;
}
//Random key array
int main() {
int s;
for (int i = 1; i < 21; i++) {
s = i * 3000;
vector<int> Arr(s);
cout << "N : " << s << "\n";
for (int i = 0; i < 10; i++) {
//Assign Random numbers to each elements
Arr.front() = rand() % Arr.size();
for (int j = 1; j < Arr.size(); j++) { Arr.at(j) = ((737 * Arr.at(j - 1) + 149) % (Arr.size() * 5)); }
//QuickSort(Arr, 0, Arr.size() - 1); <- you can switch using this instead of MergeSort(...) below
clock_t start, end;
start = clock();
MergeSort(Arr, 0, Arr.size() - 1);
end = clock() - start;
printf("%12.3f ", (double)end * 1000.0 / CLOCKS_PER_SEC);
}
cout << endl;
}
return 0;
}
And the THING is, the result is not matching with their time complexity. for example, Merge sort in(RANDOM Array)
size N=3000 prints 20 ms, but size N=60000 prints 1400~1600 ms !! it supposed to print almost 400 ms because Time complexity (Not in worse case) in Quick Sort is O(n.log(n)), isn't it? I want to know what affects to this time and how could I see the printed time that I expected.
You posted the same code in this question: Calculate Execution Times in Sort algorithm and you did not take my answer into account.
Your MergeSort function has a flaw: you duplicate the whole array in merge causing a lot of overhead and quadratic time complexity. This innocent looking definition: vector<int> u(s); defines u as a vector initialized as a copy of s, the full array.
C++ is a very powerful language, often too powerful, littered with traps and pitfalls such as this. It is a very good thing you tried to verify that your program meets the expected performance from the known time complexity of the algorithm. Such a concern is alas too rare.
Here are some guidelines:
For getting execution time:
#include <time.h>
int main()
{
struct timeval stop, start;
int arr[10000];
gettimeofday(&start, NULL);
mergeSort(arr, 0, 9999);
gettimeofday(&stop, NULL);
printf("Time taken for Quick sort is: %ld microseconds\n",
(stop.tv_sec-start.tv_sec)*1000000+stop.tv_usec-start.tv_usec);
}
I keep getting this error, and I have no clue what is wrong. I checked all variables, but all of them are defined at least somewhere
int creatures = 5;
int deathChance = 5;
int repChance = 10;
int timer = 0;
int rand = 0;
int CurrentCreatures = 0;
int b = 0;
void draw(); {
if(timer < 100)
{
b = 0;
CurrentCreatures = creatures;
while(b < CurrentCreatures)
{
rand = random(0,100);
if(rand <= repChance)
{
creatures += 1;
}
rand = random(0,100);
if(rand <= deathChance)
{
creatures -= 1;
}
b += 1;
}
println(creatures);
timer += 1;
}
}
what the program should be doing is printing the value of creatures over 100 generations (yes this is my attempt at some "life" simulator.
I think the problem lies here: void Draw(); { the ; is an end of instruction character
So it is trying to execute a function called draw, the it tries to do everything inside the {'s
possibly something like:
function draw() {
if(timer < 100) {
b = 0;
CurrentCreatures = creatures;
while(b < CurrentCreatures) {
rand = random(0,100);
if(rand <= repChance) {
creatures += 1;
}
rand = random(0,100);
if(rand <= deathChance) {
creatures -= 1;
}
b += 1;
}
println(creatures);
timer +=1;
}
}
On implementing O(N+M) complexity code for Foe Pairs problem
http://codeforces.com/contest/652/problem/C, I am getting TLE in Test Case 12.
Constraint : (1 ≤ N, M ≤ 3·105)
I am not getting, why for this constraint O(N+M) is getting TLE.
Here, is the code
#include<iostream>
#include<vector>
using namespace std;
int main()
{
int n,m;
cin>>n>>m;
std::vector<int> v(n+1);
for (int i = 0; i < n; ++i)
{
int x;
cin>>x;
v[x] = i;
}
std::vector<int> dp(n,0);
for (int i = 0; i < m; ++i)
{
int a,b;
cin>>a>>b;
if(v[a]>v[b])
swap(a,b);
dp[v[b]] = max(dp[v[b]], v[a]+1);
}
for (int i = 1; i < n; ++i)
{
dp[i] = max(dp[i], dp[i-1]);
}
long long s = 0;
for (int i = 0; i < n; ++i)
{
s+=(i+1-dp[i]);
}
cout<<s;
}
Is there anything, I am missing?
I changed all cin to scanf, it passed all test cases : http://codeforces.com/contest/652/submission/17014495
#include<cstdio>
#include<iostream>
#include<vector>
using namespace std;
int main()
{
int n,m;
scanf("%d%d", &n, &m);
//cin>>n>>m;
std::vector<int> v(n+1);
for (int i = 0; i < n; ++i)
{
int x;
//cin>>x;
scanf("%d", &x);
v[x] = i;
}
std::vector<int> dp(n,0);
for (int i = 0; i < m; ++i)
{
int a,b;
//cin>>a>>b;
scanf("%d%d", &a, &b);
if(v[a]>v[b])
swap(a,b);
dp[v[b]] = max(dp[v[b]], v[a]+1);
}
for (int i = 1; i < n; ++i)
{
dp[i] = max(dp[i], dp[i-1]);
}
long long s = 0;
for (int i = 0; i < n; ++i)
{
s+=(i+1-dp[i]);
}
cout<<s;
return 0;
}
You should always try to use scanf when the amount of input is large as it is faster.
You can read more about scanf being faster here : Using scanf() in C++ programs is faster than using cin?
I'm giving a user choices to whether sort the elements in ascending or descending order. I know my code can sorts the elements right but somewhere in main I think I'm making mistake in calling my function to print the ascending/descending element in their proper order. Or do I have to have another if statement like I have in the bubble_sort function? I need to make it so the Main function prints the final results to the user. Here's the output I'm getting:
Enter number of elements
3
Enter 3 integers
43
7
90
Enter sort order
Please enter A for ascending or D for descending order
d
Sorted list in descending order:
43
7
90
#include <stdio.h>
void bubble_sort(long [], char n);
int main()
{
long array[100], n, c;
printf("Enter number of elements\n");
scanf("%ld", &n);
printf("Enter %ld integers\n", n);
for (c = 0; c < n; c++)
scanf("%ld", &array[c]);
printf("Enter sort order\n");
fflush(stdin);
printf("Please enter A for ascending or D for descending order\n");
scanf("%ld", &n);
bubble_sort(array, n);
printf("Sorted list in descending order:\n");
for ( c = 0 ; c < n ; c++ )
{
printf("%ld\n", array[c]);
}
fflush(stdin);
getchar();
return 0;
}
void bubble_sort(long list[], char n)
{
long c, d, temp;
if(n=='a' || n=='A')
{
for (c = 0 ; c < ( n - 1 ); c++)
{
for (d = 0 ; d < n - c - 1; d++)
{
if (list[d] > list[d+1])
{
temp = list[d];
list[d] = list[d+1];
list[d+1] = temp;
}
}
}
}
if(n=='d' || n=='D')
{
long c, d, temp;
for (c = 0 ; c < ( n - 1 ); c++)
{
for (d = 0 ; d > n - c - 1; d++)
{
if (list[d] < list[d+1])
{/* Swapping */
temp = list[d];
list[d] = list[d+1];
list[d+1] = temp;
}
}
}
}
}
EDIT: Here I added a swap function just so the ascending/descending logic is more efficient. But I seem to mixed up use of the variables which I think is a big problem. Would anyone point out and help me understand where and why I'd need to use those variables? Thanks much!
#include <stdio.h>
void bubble_sort(int list[], int n, char c);
void swap(int x, int y, int array[]);
int main()
{
int array[100], j, i;
char c;
printf("Enter number of elements\n");
scanf("%d", &j);
printf("Enter %d integers\n", j);
for (i = 0; i < j; i++)
scanf("%d", &array[i]);
printf("Please enter A for ascending or D for descending order\n");
scanf("%s", &c);
bubble_sort(array, j, i);
printf("Sorted list in descending order:\n");
for (i = 0 ; i < j ; i++ )
{
printf("%d\n", array[i]);
}
getchar();
return 0;
}
void bubble_sort(int list[], int n, char c)
{
int i, j;
if(c=='a' || c=='A'){
for (i = 0; i < (n - 1); i++){
for (j = 0; j < (n - i) - 1; j++){
if (list[i] > list[j])
{
swap(i, j, list); }
}
}
}
if(c=='d' || c=='D') {
for (i = 0 ; i < ( n - 1 ); i++) {
for (j = 0 ; j > (n - i) - 1; j++) {
if (list[i] < list[j])
{
swap(i, j, list);
}
}
}
}
}
void swap(int x, int y, int array[])
{
int hold; //temp hold a number
hold = array[x];
array[x] = array[y];
array[y] = hold;
}
In this statements
printf("Please enter A for ascending or D for descending order\n");
scanf("%ld", &n);
you are overwritting the value stored in n that before these statements denoted the number of the elements in the array. You should declare one more variable of type char and use it for this code snippet.
Also the sort function should be declared as
void bubble_sort(long list[], int n, char c );
where n is the array size and c is either 'A' or 'D'
EDIT: Your new code contains many typos. Try the following
#include <stdio.h>
void swap( int x, int y, int array[] )
{
int hold; //temp hold a number
hold = array[x];
array[x] = array[y];
array[y] = hold;
}
void bubble_sort( int list[], int n, char c )
{
int i, j;
if ( c == 'a' || c == 'A' )
{
for ( i = 0; i < n - 1; i++ )
{
for ( j = 0; j < n - i - 1; j++ )
{
if ( list[j] > list[j+1] )
{
swap( j, j + 1, list);
}
}
}
}
if ( c=='d' || c=='D' )
{
for ( i = 0 ; i < n - 1; i++ )
{
for ( j = 0 ; j < n - i - 1; j++ )
{
if ( list[j] < list[j+1] )
{
swap( j, j + 1, list);
}
}
}
}
}
int main(void)
{
int array[100], j, i;
char c;
printf("Enter number of elements: ");
scanf( "%d", &j);
printf( "Enter %d integers\n", j );
for ( i = 0; i < j; i++ ) scanf( "%d", &array[i] );
printf("Please enter A for ascending or D for descending order: ");
scanf( " %c", &c );
printf( "%c\n", c );
bubble_sort( array, j, c );
printf( "Sorted list in the selected order:\n" );
for ( i = 0; i < j; i++ )
{
printf( "%d ", array[i] );
}
puts( "" );
return 0;
}
I have a Codility test to take soon.
I was trying to find a modification in the code to avoid EXTREME LARGE NUMBERS ERROR by using LONG instead of INT... but this did not work.
Has anybody tried using CODILITY demo test and get a 100?
I went through previous posts but no solution to this particular problem.
MY CODE: COMPLEXITY O(N)... Still I got 94.
// you can also use includes for example:
// #include <algorithm>
#include<iostream>
#include<vector>
#include<math.h>
int equi ( const vector<int> &A ) {
if((int)A.size()==0)
return -1;
long int sum_l = A[0];
long int total_sum =0;
for(int i =0; i<(int)A.size();i++){
total_sum = total_sum + A[i];
}
int flag =0;
total_sum = total_sum -A[0];
if(total_sum == 0)
return 0;
for(int i=1; i<(int)A.size()-1;i++){
total_sum = total_sum - A[i];
if(sum_l ==total_sum){
flag=1;
return i;
}
sum_l= sum_l + A[i];
}
if(sum_l ==0)
return (int)A.size()-1;
if(flag ==0)
return -1;
}
I used long long, and I had not problem.
Try this one.
int left = A[0];
int right = 0;
for(int i: A){
right += i;
}
right -= left;
int diff = Math.abs(left - right);
for (int i = 1; i < A.length-1; i++) {
left += A[i];
right -= A[i];
int a = Math.abs(left - right);
if(diff > a){
diff = a;
}
}
return diff;