#include<stdio.h>
int main(void)
{
    long int a,b,c,i;
    while(scanf("%d %d",&a,&b)!=EOF)
    {               c=a;
                    for(i=1;b>=a;i++)
                    {
                    a=a+c+1;
                    c++;
                    }
                    printf("%d",i);
    }
    
    
    return 0;
    }

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