题解 | #数组分组#

let line

while(line = readline()){
    let num = parseInt(line);
    let count = 0
    for(let i=0;i<=num;i++){
        let idot = String(i)
        if(idot.endsWith('0')||idot.endsWith('1')||idot.endsWith('5')||idot.endsWith('6')){
            let power = Math.pow(i,2);
            let str = String(power)
            if(str.endsWith(idot)){
                count++
            }
        }
    }
    console.log(count)
}