#include <stdio.h>

#define MAX_N 100000

int aib[MAX_N + 1];

void update( int i, int a, int n ) {
    while ( i <= n ) {
        aib[i] += a;
        i += i & -i;
    }
}

int query( int i ) {
    int s;

    s = 0;
    while ( i > 0 ) {
        s += aib[i];
        i -= i & -i;
    }

    return s;
}

int main() {
    FILE *fin, *fout;
    int n, q, tip, a, s, f, p, st, dr, mij, i;

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

    fscanf( fin, "%d%d", &n, &q );
    for ( i = 1; i <= n; i++ ) {
        fscanf( fin, "%d", &a );
        update( i, a, n );
    }

    fout = fopen( "aib.out", "w" );

    for ( i = 0; i < q; i++ ) {
        fscanf( fin, "%d", &tip );
        if ( tip == 0 ) {
            fscanf( fin, "%d%d", &p, &a );
            update( p, a, n );
        }
        else if ( tip == 1 ) {
            fscanf( fin, "%d%d", &s, &f );
            fprintf( fout, "%d\n", query( f ) - query( s - 1 ) );
        }
        else {
            fscanf( fin, "%d", &s );

            st = 1;
            dr = n + 1;
            while ( dr - st > 1 ) {
                mij = (st + dr) / 2;
                if ( query( mij ) > s )
                    dr = mij;
                else
                    st = mij;
            }

            fprintf( fout, "%d\n", query( st ) == s ? st : -1 );
        }
    }

    return 0;
}