Next greater element(stack)

#1

will you help me to correct the order

#2

hi @abhinavssr2003_eab0717682969e5c,
try
5
5 5 5 5 5

ans is -1 -1 -1 -1 -1

#3

sir the question is different…it is next greater element

#4

hi @abhinavssr2003_eab0717682969e5c refer

#include <bits/stdc++.h> 
using namespace std; 

// Function to print Next Greater Element for each element of the array
void nextGreater(int arr[], int n) 
{ 
 // Write Code here
 stack<int> s;
    int res[n];
    for (int i = n - 1; i >= 0; i--) {
        /* if stack is not empty, then
        pop an element from stack.
        If the popped element is smaller
        than next, then
        a) print the pair
        b) keep popping while elements are
        smaller and stack is not empty */
        if (!s.empty()) {
            while (!s.empty() && s.top() <= arr[i]) {
                s.pop();
            }
        }
        res[i] = s.empty() ? -1 : s.top();
        s.push(arr[i]);
    }
    for (int i = 0; i < n; i++)
        cout << arr[i] << "," << res[i] << endl;
} 

// The Main Function
int main() 
{ 
    int t;
    cin>>t;
    while(t--){
        int n;
        cin>>n;
        int arr[n];
        for(int i=0; i<n; i++){
            cin>>arr[i];
        }
        nextGreater(arr, n); 
    }
	
	return 0; 
}
#5

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