题解 | 金币

#include <stdio.h>
int main()
{
    int k = 0;
    int days = 0;//记录已经累计的天数
    int total = 0;//记录发放的总金币数量
    int stage = 1;//记录发放金币的阶段
    scanf("%d",&k);//输入总天数

    while(1)
    {
        if(days + stage <= k)
        {
            total += stage * stage;
            days += stage;
            stage++;
        }
        else 
        {
            int remain = k - days;
            total += remain * stage;
            break;
        }
    }

    printf("%d",total);

    return 0;
}