2025-11-03 19:43:44 +09:00

18 lines
496 B
TypeScript

export {};
const square = (N: number, point: number[][]): string => {
let temp = 0;
for(let i=0; i<N; i++) {
temp += point[i][0]*point[i+1][1] - point[i+1][0]*point[i][1];
}
return (0.5*Math.abs(temp)).toFixed(1);
}
const input = require("fs").readFileSync(0).toString().trim().split('\n');
const N = Number(input[0]);
let point: number[][] = [];
for(let i=1; i<=N; i++) point.push(input[i].split(" ").map(Number));
point.push(point[0]);
console.log(square(N, point));