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#1

Kindly ignore the previous doubt. I’m getting TLE on test case 3. Can you tell me where I’m going wrong? Here is my code:(Assume all the header files are included)

using namespace std;

int main() {

int n,k;
cin>>n>>k;
vector<int> v;
v.reserve(100000);
for(int i=0; i<n; i++){
    int no;
    cin>>no;
    v.push_back(no);
}
int i=0;
while(k > 0){
    auto max = max_element(v.begin()+i, v.end());
    if(v.begin()+i == max){
        i++;
    }else{
        iter_swap(v.begin()+i, max); 
        k--;
        i++;
    }
}

for(auto it = v.begin(); it != v.end(); it++){
    cout<<*(it)<<" ";
}
return 0;

}

#2

hello @JaiGaur
your code time complexity is O(k*n) thats why it is giving tle.

try to optimise it using hashing.

ok ,i m closing ur last thread

#3

Sir, any other approach?

#4

note that the given array will always contain permutation of the first N natural numbers. So we will prepare a map which will contain element as the key and the index at which it is present as the value.

Algorithm

  1. Create the map by filling the number as the key and the index at which it is present as the value
  2. Iterate over the whole array.
  3. For element at a particular index m we will check if it is present at its best spot or not.
  4. The best spot of any number num is the N-num index of the array.
  5. If the number is not present at its best spot then we will swap the number with element present at that spot.
  6. As we have stored the index of every element in the map we can easily retrieve that from the map to get the swap done.
#5

Sir, according to you what could be the division and level(A/B/C/D/E/F/G) of this question on codeforces?

#6

div2 B. . . . . . . . . . . . . . .

#7

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