function processData(input) {
var arr,k_1_speed,k_2_speed,k_1,k_2;
arr = input.split(' ');
k_1_speed = arr[1];
k_1 = arr[0];
k_2_speed = arr[3];
k_2 = arr[2];
for (let i = k_1 ; i < 100 ; i += k_1_speed ) {
console.log(i);
}
console.log(k_1);
}
function processData(input) {
var arr,k_1_speed,k_2_speed,k_1,k_2,i,arr1,arr2;
arr = input.split(' ');
arr1 = [];
arr2 = [];
k_1_speed = Number(arr[1]);
k_1 = Number(arr[0]);
k_2_speed = Number(arr[3]);
k_2 = Number(arr[2]);
for ( i = k_1 ; i < 100000; i += k_1_speed ) {
arr1.push(i);
}
for ( i = k_2 ; i < 100000 ; i += k_2_speed ) {
arr2.push(i);
}
for (let k = 0; k < 10001; k++) {
if (Number(arr1[k]) == Number(arr2[k])) {
console.log("YES");
break;
}
if (k==10000){
console.log("NO");
}
}
}
process.stdin.resume();
process.stdin.setEncoding("ascii");
_input = "";
process.stdin.on("data", function (input) {
_input += input;
});
process.stdin.on("end", function () {
processData(_input);
});
process.stdin.resume();
process.stdin.setEncoding('ascii');
var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;
process.stdin.on('data', function (data) {
input_stdin += data;
});
process.stdin.on('end', function () {
input_stdin_array = input_stdin.split("\n");
main();
});
function readLine() {
return input_stdin_array[input_currentline++];
}
/////////////// ignore above this line ////////////////////
function main() {
var x1_temp = readLine().split(' ');
var x1 = parseInt(x1_temp[0]);
var v1 = parseInt(x1_temp[1]);
var x2 = parseInt(x1_temp[2]);
var v2 = parseInt(x1_temp[3]);
var l1 = x1;
var l2 = x2;
for (var i=0; i< 10001; i++){
l1+=v1;
l2+=v2;
if(l1 == l2){
console.log("YES");
return;
}
}
console.log("NO");
}
