const rl = require("readline").createInterface({ input: process.stdin }); var iter = rl[Symbol.asyncIterator](); const readline = async () => (await iter.next()).value; void (async function () { // 有点取巧了 while ((line = await readline())) { let tokens = line.split(" "); const a = +tokens[0]; const b = +tokens[1]; if (a === b) { console.log(0); } else if (b === 0) { console.log(1); } else if (a === 0) { console.log(2); } else if (a + b === 0) { console.log(3); } else { console.log(-1); } } })();