Steps

Steps

Description



One steps through integer points of the straight line. The length of a step must be nonnegative and can be by one bigger than, equal to, or by one smaller than the length of the previous step.

What is the minimum number of steps in order to get from x to
y? The length of the first and the last step must be 1.

Input and Output 

Input consists of a line containing n, the number of test cases. For each test case, a line follows with two integers:
0

x

y
< 231. For each test case, print a line giving the minimum number of steps to get from
x to y.

Sample Input 

3
45 48
45 49
45 50

Sample Output 

3
3
4

大意：
给出X， Y求出X到Y所需的最小步数；

第一步和最后一步的步宽均为1,中间的每步都是前面的一步的步宽+1,+0,-1；

要点：

观察最小步数可发现

最小步数：0 1 2 3 4 5 6 7 8 9 10 11 12

        个数：1 1 1 2 2 3 3 4 4 5  5    6   6

即最小步数为0的有1个数，最小步数为10有5个数；

除最小步数为0的外其他所对应的个数总和即是Y-X的值；

比如输入0 6则Y-X=6；

1+1+2+2 = 6 >= 6 则输出最后一个2所对应的4；

#include <stdio.h>

int main(){
int num;
int n1, n2;
scanf ("%d", &num);
getchar();
while (num --){
scanf ("%d %d", &n1, &n2);
getchar();
int step = n2 - n1;
int x = 0;
int min;
for (int i = 0, j = 0;; i++){
x += j;
if (x >= step){
min = i;
break;
}
else {
if (i % 2 == 0)
j++;
}
}
printf ("%d\n", min);
}
return 0;

}