hrbustOJ 围困(判断点是否在三角形内)

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/*

*  题目要求：判断点是否在三角形内

*  可利用叉乘判断拐向来解决 

*  auther:Try86

*/



#include <cstdio>

#include <iostream>



using namespace std;



struct point {

    int x;

    int y;

}A, B, C, D;



int crossProd(point A, point B, point C) {

    return (B.x-A.x)*(C.y-A.y) - (B.y-A.y)*(C.x-A.x);

}



bool inTrangle() {

    if (crossProd(D, A, B)<0 && crossProd(D, B, C)<0 && crossProd(D, C, A)<0) return true;

    if (crossProd(D, A, B)>0 && crossProd(D, B, C)>0 && crossProd(D, C, A)>0) return true;

    return false;

}



int main() {

    while (scanf("%d%d%d%d%d%d%d%d", &A.x, &A.y, &B.x, &B.y, &C.x, &C.y, &D.x, &D.y) != EOF) {

        bool yes = inTrangle();

        if (yes) printf ("Die\n");

        else printf ("Live\n");

    }

    return 0;

}