Having problem in memset

general
,
1

I am solving a problem josephus problem where i require to set all elements of array to 1, but by using memset its not happening.I tried printing the array it has been filled by a random number. My solution to problem is correct(i placed 1 manually and checked).I have used memset before too but never faced this problem.(i tried running it on cses and clion).
the line i used is:
int arr[n];
memset (arr,1,sizeof(arr));

My code is provided below:(line 44)

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

long long multi(long long a, long long b, long long mod){
    return (a * b) % mod;
}

long long power(long long a, long long b, long long mod){
    long long powans = 1;

    for(; b > 0; a = multi(a, a, mod), b /= 2) if(b % 2 == 1) powans = multi(powans, a, mod);

    return powans;
}

void fastscan(int &x)
{
    bool neg=false;
    register int c;
    x =0;
    c=getchar();
    if(c=='-')
    {
        neg = true;
        c=getchar();
    }
    for(;(c>47 && c<58);c=getchar())
        x = (x<<1) + (x<<3) +c -48;
    if(neg)
        x *=-1;
}

int gcd(int a,int b){
    if(a%b==0)
        return b;
    else
        return gcd(b,a%b);
}

void solve(){
    int n;
    fastscan(n);
    int arr[n];
    memset (arr,1,sizeof(arr));
    int count=0;
    int del=0;
    int i=0;
    while(del!=n){
        if(arr[i]==1){
            if(count==1){
                cout<<i+1<<" ";
                count=0;
                del++;
                arr[i]=0;
            }
            else
                count++;
        }
        i++;
        if(i==n)
            i=0;
    }
}
int main(){

#ifndef ONLINE_JUDGE
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
    freopen("error.txt","w",stderr);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    solve();
    return 0;
}

Any help is appreciated thanks.

2

memset works only for -1,0,+\infty → 0x3f,-\infty → 0xc0. fill_n() is a wiser choice if the array in one-dimensional

2 Likes
3

Thank you for the help.