square root segmentation

#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;

struct node{

    //int start=0, end=0, sum=0;
    int start, end, sum;
} blockSum[100];


void sumUp(int number[], int size, int blockSize){




    int blockIndx=-1;

    for (int i=0; i<size; i++){
        if((i % blockSize) == 0){
            blockIndx++;

            blockSum[blockIndx].start=i;
            blockSum[blockIndx].end=i+blockSize-1;

        }

        blockSum[blockIndx].sum+=number[i];

    }

}

int query(int qstart, int qend, int number[],int blockSize){

    int totalsum=0;

    for(int i=0; i<blockSize; i++){

        if(qstart<=blockSum[i].start  &&  blockSum[i].end<=qend ){

            totalsum+=blockSum[i].sum;
            cout<<endl<<totalsum<<endl;

            cout<<'w';
        }


    else if(qstart<=blockSum[i].start && qend <=blockSum[i].end){

                for(int j=blockSum[i].start; j<=qend; j++)
                    totalsum+=number[j],cout<<'x';
        }

    else if(qstart>=blockSum[i].start && blockSum[i].end <=qend){

                for(int j=qstart; j<=blockSum[i].end; j++)
                    totalsum+=number[j],cout<<'y';
        }



    //else if(qstart<=blockSum[i].start && blockSum[i].end <=qend){


        //}

    }

    return totalsum;
}

int main(int argc, char **argv)
{


    int number[]={1,2,3,4,5,6,7,8,9};

    int size = sizeof(number) / sizeof(number[0]);


    int blockSize = sqrt(size);

    cout<<blockSize<<endl;

    sumUp(number, size, blockSize);

    for(int i =0; i<blockSize; i++){
        cout<<blockSum[i].sum<<" ";
        cout<<blockSum[i].start<<" ";
        cout<<blockSum[i].end<<endl<<" ";
    }
    cout<<endl<<query(1,4,number, blockSize);
    cout<<endl<<query(0,5,number, blockSize);
    //cout<<endl<<query(3,5,number, blockSize);
    //cout<<endl<<query(0,5,number, blockSize);
    //cout<<endl<<query(3,8,number, blockSize);
    //cout<<endl<<query(0,8,number, blockSize);
    //cout<<endl<<query(0,4,number, blockSize);
    //cout<<endl<<query(0,5,number, blockSize);
    //cout<<endl<<query(2,5,number, blockSize);
    //cout<<endl<<query(6,8,number, blockSize);


    return 0;
}