Submission #705462

#	Time	Username	Problem	Language	Result	Execution time	Memory
705462		YassineBenYounes	Stove (JOI18_stove)	C++17	100 / 100	20 ms	2172 KiB

stove

/*
ID: Yassine BenYounes
TASK: guard
LANG: C++
*/
#include<bits/stdc++.h>
 
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef double db;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define pbds tree<int, null_type, less<int>,rb_tree_tag, tree_order_statistics_node_update>
using namespace __gnu_pbds;
ll gcd(ll a , ll b) {return b ? gcd(b , a % b) : a ;} // greatest common divisor (PGCD)
ll lcm(ll a , ll b) {return (a * b) / gcd(a , b);} // least common multiple (PPCM)
int dx[8] = {1, 0, 0, -1, 1, 1, -1, -1};
int dy[8] = {0, 1, -1, 0, 1, -1, -1, 1};
#define endl "\n"
#define ss second
#define ff first
#define all(x) (x).begin() , (x).end()
#define pb push_back
#define vi vector<int>
#define vii vector<pair<int,int>>
#define vl vector<ll>
#define vll vector<pair<ll,ll>>
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pdd  pair<double,double>
#define vdd  vector<pdd>
#define speed ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
////////////////////Only Clear Code//////////////////////////

vi primes;

const int ppppp = 3e6+9;
ll mod = 1e9+7;
bool prime[ppppp];
ll fact[ppppp];
void sieve(int n){
    memset(prime, 1, sizeof prime);
    prime[1] = 0;
    for(int i = 2; i < n;i++){
        if(!prime[i])continue;
        primes.pb(i);
        for(int j = 2*i;j < n;j+=i){
            prime[j] = 0;
        }
    }
}

vi factors(int n){
    vi res;
    for(int i = 0; i < primes.size() && primes[i]*primes[i] <= n;i++){
        if(n % primes[i] == 0)res.pb(primes[i]);
        while(n % primes[i] == 0){
            n /= primes[i];
        }
    }
    if(n > 1)res.pb(n);
    return res;
}

ll binpow(ll a, ll b){
    if(b == 0)return 1;
    ll x = binpow(a, b/2) % mod;
    ll g = x*x;
    g %= mod;
    if(b%2 == 0)return g;
    g*=a;
    g%=mod;
    return g;
}

ll modinv(ll a){
    return binpow(a, mod-2);
}

ll sub(ll a, ll b){
    ll c = (a%mod)-(b%mod);
    while(c < 0)c+=mod;
    return c;
}
ll add(ll a, ll b){
    return (((a%mod)+(b%mod)) % mod);
}

ll mult(ll a, ll b){
    a %= mod;
    b %= mod;
    ll c = a*b;
    c %= mod;
    return c;
}

ll divide(ll a, ll b){
    a %= mod;
    b = modinv(b) % mod;
    ll c = a*b;
    c%=mod;
    return c;
}

void pre_fact(int n){
    fact[0]=1;
    for(int i = 1; i < n;i++){
        fact[i] = mult(fact[i-1],i);
    }
}

ll choose(ll k, ll n){
    ll c = mult(mult(fact[n],modinv(fact[k])), modinv(fact[n-k]));
    return c;
}

ll perm(ll n){
    return fact[n];
}

ll arrange(ll k, ll n){
    ll c = mult(fact[n],modinv(fact[n-k]));
    return c;
}

void init(){
    #ifndef ONLINE_JUDGE
 
freopen("input.txt", "r", stdin);
 
freopen("output.txt", "w", stdout);
 
#endif // ONLINE_JUDGE
}

const int mx = 50;
const int LOG = 25;
const int inf = 1e9;

int arr[mx];

void run_case(){
    int n, k;cin >> n >> k;vi v;
    for(int i = 0; i < n;i++){
        cin >> arr[i];
        if(i>0)v.pb(arr[i]-arr[i-1]-1);
    }
    sort(all(v), greater<int>());
    ll ans = 0;
    for(int i = 0; i < min(n-1, k-1);i++){
        ans += v[i];
    }
    cout << arr[n-1] - arr[0] +1 - ans << endl;
}

int main(){
    //freopen("promote.in", "r", stdin);
    //freopen("promote.out", "w", stdout);
    //init();
    speed;
    //sieve(ppppp);
    //pre_fact(ppppp);
    int t;
    //cin >> t;
    t=1;
    while(t--){
        run_case();
    }
}

/*
    NEVER GIVE UP!
    DOING SMTHNG IS BETTER THAN DOING NTHNG!!!
    Your Guide when stuck:
    - Continue keyword only after reading the whole input
    - Don't use memset with testcases
    - Check for corner cases(n=1, n=0)
    - Check where you declare n(Be careful of declaring it globally and in main)
*/

Compilation message (stderr)

stove.cpp: In function 'std::vector<int> factors(int)':
stove.cpp:57:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |     for(int i = 0; i < primes.size() && primes[i]*primes[i] <= n;i++){
      |                    ~~^~~~~~~~~~~~~~~
stove.cpp: In function 'void init()':
stove.cpp:131:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  131 | freopen("input.txt", "r", stdin);
      | ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
stove.cpp:133:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  133 | freopen("output.txt", "w", stdout);
      | ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 50 / 50