HackerEarth: Kinako Bread (DS- Greedy, 2 pointers )

HackerEarth: Kinako Bread (DS- Greedy, 2 pointers )
///==================================================///
///                HELLO WORLD !!                    ///
///                  IT'S ME                         ///
///               BISHAL GAUTAM                      ///
///         [ bsal.gautam16@gmail.com ]              ///
///==================================================///
#include<bits/stdc++.h>
#define X first
#define Y second
#define mpp make_pair
#define nl printf("\n")
#define SZ(x) (int)(x.size())
#define pb(x) push_back(x)
#define pii pair<int,int>
#define pll pair<ll,ll>
///---------------------
#define S(a) scanf("%d",&a)
#define P(a) printf("%d",a)
#define SL(a) scanf("%lld",&a)
#define S2(a,b) scanf("%d%d",&a,&b)
#define SL2(a,b) scanf("%lld%lld",&a,&b)
///------------------------------------
#define all(v) v.begin(),v.end()
#define CLR(a) memset(a,0,sizeof(a))
#define SET(a) memset(a,-1,sizeof(a))
#define fr(i,a,n) for(int i=a;i<=n;i++)
using namespace std;
typedef long long ll;
///==========CONSTANTS=============///
///  Digit     0123456789012345678 ///
#define MX     100005
#define inf    1000000010
#define MD     1000000000LL
#define eps    1e-9
///===============================///

vector<int>v[MX+2];
int L[MX+2],R[MX+2];
int c1[MX+2],c2[MX+2];///Connections- Least connection & Most connections;
set<pii>sl,sr;/// storing current indices of Least & most for every elements

ll Calc( ) {
    int rgBg=(*sr.begin()).X;
    int lfEd=(*sl.rbegin()).X;
    return (rgBg-lfEd);
}
int s[MX+2];
int ar[MX+2];
int main() {
    int tc,cs=1,i,j,k,q,n,m,x,y;
    //S(tc);
    tc=1;
    while(tc--) {
        S2(n,m);
        fr(i,1,m)v[i].clear();
        fr(i,1,n) {
            S(x);
            ar[i]=x;
            v[ x ].pb( i );
        }
        fr( i,1,m ) {
            S2( L[i],R[i] );
            R[i]++;
        }
        int i,f=1;
        sl.clear();
        sr.clear();
        CLR(s);/// s-arry for tot times 'i' has been taken
        /// Pre;
        for(i=1; i<=m; i++) {
            int sz=SZ( v[i] );
            if( L[i]+s[i]>sz ) {
                f=0;
                break;
            } else c1[ i ]=v[i][ L[i]+s[i]-1 ];
            if( R[i]+s[i]>sz ) {
                c2[i]=n+1;
            } else c2[i]=v[i][ R[i]+s[i]-1];
            sl.insert( mpp( c1[i],i ) );
            sr.insert( mpp( c2[i],i ) );
            s[i]++;
        }
        if(f==0) {
            printf("0\n");
            continue;
        }
        ll tp=max( Calc( ),0LL );
        /// Now, Procedure of deleting from last;
        ll sm=tp;
        int j=1;
        while(j<=n) {
            i=ar[j];
            ///Del ar[i] && update latest info for ar[i];
            sl.erase( mpp( c1[i],i ) );
            sr.erase( mpp( c2[i],i ) );
            int sz=SZ( v[i] );
            if( L[i]+s[i]>sz ) {
                break;
            } else c1[ i ]=v[i][ L[i]+s[i]-1 ];
            if( R[i]+s[i]>sz ) {
                c2[i]=n+1;
            } else c2[i]=v[i][ R[i]+s[i]-1];
            sl.insert( mpp( c1[i],i ) );
            sr.insert( mpp( c2[i],i ) );
            s[i]++;
            ll tp=Calc();
            sm+=max( tp,0LL );
            j++;
        }
        printf("%lld\n",sm);
    }
    return 0;
}