'use strict';

function area_of_circle(r, pi) { var r1 = 1; var pi1 = 3.14; if(typeof r === 'number' && r>0) { r1 = r;

} if(typeof pi === 'number' && pi >= 3.14 && pi <3.15){ pi1 = pi; } return pi1r1r1; } // 测试: if (area_of_circle(2) === 12.56 && area_of_circle(2, 3.1416) === 12.5664) { alert('测试通过'); } else { alert('测试失败'); }