A. Triangle

time limit per test

2 seconds

memory limit per test

64 megabytes

input

standard input

output

standard output

Johnny has a younger sister Anne, who is very clever and smart. As she came home from the kindergarten, she told his brother about the task that her kindergartener asked her to solve. The task was just to construct a triangle out of four sticks of different colours. Naturally, one of the sticks is extra. It is not allowed to break the sticks or use their partial length. Anne has perfectly solved this task, now she is asking Johnny to do the same.

The boy answered that he would cope with it without any difficulty. However, after a while he found out that different tricky things can occur. It can happen that it is impossible to construct a triangle of a positive area, but it is possible to construct a degenerate triangle. It can be so, that it is impossible to construct a degenerate triangle even. As Johnny is very lazy, he does not want to consider such a big amount of cases, he asks you to help him.

Input

The first line of the input contains four space-separated positive integer numbers not exceeding 100 — lengthes of the sticks.

Output

Output TRIANGLE if it is possible to construct a non-degenerate triangle. Output SEGMENT if the first case cannot take place and it is possible to construct a degenerate triangle. Output IMPOSSIBLE if it is impossible to construct any triangle. Remember that you are to use three sticks. It is not allowed to break the sticks or use their partial length.

Sample test(s)

input

4 2 1 3

output

TRIANGLE

input

7 2 2 4

output

SEGMENT

input

3 5 9 1

output

IMPOSSIBLE

解题说明：此题就是判断从4根棍子中选择3根是否能够构成三角形，至于三角形这里有普通三角形和退化三角形之分，退化三角形解释如下：

退化三角形（degenerate triangle）是个面积为零的三角形，或换句话说，是个三点位于一线上的三角形。如果我们传入一个退化三角形到渲染管线，则该三角形显示为空。

做法是先对输入线段排序，然后分情况判断即可。

#include<iostream>#include<map>#include<string>#include<algorithm>#include<cstdio>#include<cmath>using namespace std;int main(){    int i,a[4];    for(i=0;i<4;i++){scanf("%d",&a[i]);}sort(a,a+4);    if(a[0]+a[1]>a[2]||a[1]+a[2]>a[3]){printf("TRIANGLE\n");}    else if(a[0]+a[1]==a[2]||a[1]+a[2]==a[3])     { printf("SEGMENT\n");}else{printf("IMPOSSIBLE\n");}return 0;}