That was actually very helpful. I was able to convert that idea into this code.

for(j=a[i]; j<b[i]; j++){ /* i<=t-1; */
    c = sqrt(j);
    d = c*c;

    if(d==j){
        s += 1; /* number of squares */
        j = b[i];
    }
}

while(d<=b[i]){
    c++;
    d = c*c;

    if(d<=b[i])
        s += 1;
}

I didn't use /* text */ in my code. It's just there for understanding.