Submission #447649

#	Time	Username	Problem	Language	Result	Execution time	Memory
447649		cpp219	Growing Vegetables is Fun 4 (JOI21_ho_t1)	C++14	100 / 100	127 ms	7072 KiB

Main

#pragma GCC optimization O2
#pragma GCC optimization "unroll-loop"
#pragma target ("avx2")

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define fs first
#define sc second
using namespace std;
typedef pair<ll,ll> LL;
const ll N = 2e5 + 9;
const ll Log2 = 21;
const ll inf = 1e16 + 7;

ll n,a[N],prvL[N],prvR[N];

bool chk(ll m){
    ll L = 1,R = n;
    for (ll i = 2;i <= n;i++){
        ll prv = a[i - 1] + prvL[i - 1];
        prvL[i] = max(prvL[i - 1],max(0ll,prv - a[i] + 1));
        if (prvL[i] > m) break; L = i;
    }
    for (ll i = n - 1;i > 0;i--){
        ll prv = a[i + 1] + prvR[i + 1];
        prvR[i] = max(prvR[i + 1],max(0ll,prv - a[i] + 1));
        if (prvR[i] > m) break; R = i;
    }
    return (R <= L);
}

int main(){
    ios_base::sync_with_stdio(NULL); cin.tie(0); cout.tie(0);
    #define task "tst"
    if (fopen(task".INP","r")){
        freopen(task".INP","r",stdin);
        //freopen(task".OUT","w",stdout);
    }
    cin>>n;
    for (ll i = 1;i <= n;i++) cin>>a[i];
    ll l,m,h; l = 0;h = inf;
    while(l <= h){
        m = (l + h)/2;
        if (chk(m)) h = m - 1;
        else l = m + 1;
    }
    cout<<l;
}

Compilation message (stderr)

Main.cpp:1: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    1 | #pragma GCC optimization O2
      | 
Main.cpp:2: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    2 | #pragma GCC optimization "unroll-loop"
      | 
Main.cpp:3: warning: ignoring '#pragma target ' [-Wunknown-pragmas]
    3 | #pragma target ("avx2")
      | 
Main.cpp: In function 'bool chk(long long int)':
Main.cpp:23:9: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   23 |         if (prvL[i] > m) break; L = i;
      |         ^~
Main.cpp:23:33: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   23 |         if (prvL[i] > m) break; L = i;
      |                                 ^
Main.cpp:28:9: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   28 |         if (prvR[i] > m) break; R = i;
      |         ^~
Main.cpp:28:33: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   28 |         if (prvR[i] > m) break; R = i;
      |                                 ^
Main.cpp: In function 'int main()':
Main.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen(task".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 40 / 40
• Subtask 2: 60 / 60