Submission #759610

#	Time	Username	Problem	Language	Result	Execution time	Memory
759610		LucaIlie	Sum Zero (RMI20_sumzero)	C++17	0 / 100	1 ms	340 KiB

sumzero

#include <stdio.h>
#include <unordered_map>

#define MAX_N 400000
#define MAX_Q 400000
#define MAX_LOG_N 18

using namespace std;

int last0[MAX_N + 2], last[MAX_N + 2], l[MAX_Q], r[MAX_Q], ans[MAX_Q];
unordered_map <int, int> mp;

int main() {
    FILE *fin, *fout;
    int n, q, a, sp, niv, b, i;

    fin = fopen( "sumzero.in", "r" );

    fscanf( fin, "%d", &n );
    sp = 0;
    mp[sp] = 1;
    for ( i = 1; i <= n; i++ ) {
        fscanf( fin, "%d", &a );
        sp += a;
        if ( mp[sp] > 0 )
            last0[mp[sp]] = i;
        mp[sp] = i + 1;
    }

    fscanf( fin, "%d", &q );
    for ( i = 0; i < q; i++ ) {
        fscanf( fin, "%d%d", &l[i], &r[i] );
        ans[i] = 0;
    }

    fclose( fin );

    for ( i = 1; i <= n + 1; i++ ) {
        if ( last0[i] == 0 )
            last0[i] = n + 1;
    }

    for ( i = n; i >= 1; i-- )
        last0[i] = last0[i] < last0[i + 1] ? last0[i] : last0[i + 1];

    for ( niv = MAX_LOG_N; niv >= 0; niv-- ) {
        for ( i = 1; i <= n; i++ )
            last[i] = last0[i];
        for ( b = 1; b <= niv; b++ ) {
            for ( i = 1; i <= n; i++ )
                last[i] = last[i] + 1 > n ? n + 1 : last[last[i] + 1];
            last[n + 1] = n + 1;
        }
        for ( i = 0; i < q; i++ ) {
            if ( last[l[i]] <= r[i] ) {
                ans[i] += (1 << niv);
                l[i] = last[l[i]] + 1;
            }
        }
    }

    fout = fopen( "sumzero.out", "w" );
    for ( i = 0; i < q; i++ )
        fprintf( fout, "%d\n", ans[i] );
    fclose( fout );

    return 0;
}

Compilation message (stderr)

sumzero.cpp: In function 'int main()':
sumzero.cpp:19:11: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |     fscanf( fin, "%d", &n );
      |     ~~~~~~^~~~~~~~~~~~~~~~~
sumzero.cpp:23:15: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |         fscanf( fin, "%d", &a );
      |         ~~~~~~^~~~~~~~~~~~~~~~~
sumzero.cpp:30:11: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     fscanf( fin, "%d", &q );
      |     ~~~~~~^~~~~~~~~~~~~~~~~
sumzero.cpp:32:15: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |         fscanf( fin, "%d%d", &l[i], &r[i] );
      |         ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 22
• Subtask 2: 0 / 39
• Subtask 3: 0 / 39