function Main(input) {
	input = input.split("\n");
	var s = input[1];
	var n = parseInt(input[0], 10);
    var toTest = [['S', 'S'], ['S', 'W'], ['W', 'S'], ['W', 'W']];
    for (var t = 0; t < 4; t++) {
        var arr = toTest[t];
        for (var i = 1; i < n-1; i++) {
            if (s[i] == 'o') {
                if (arr[i] == 'S') {
                    if (arr[i-1] == 'S') {
                        arr.push('S');
                    } else {
                        arr.push('W');
                    }
                } else {
                    if (arr[i-1] == 'S') {
                        arr.push('W');
                    } else {
                        arr.push('S');
                    }
                }
            } else {
                if (arr[i] == 'S') {
                    if (arr[i-1] == 'S') {
                        arr.push('W');
                    } else {
                        arr.push('S');
                    }
                } else {
                    if (arr[i-1] == 'S') {
                        arr.push('S')
                    } else {
                        arr.push('W');
                    }
                }
            }
        }
    }
    var failCount = 0;
    for (var t = 0; t < 4; t++) {
        var fail = false;
        var arr = toTest[t];
        for (var i = 0; i < n; i++) {
            var prev = i - 1;
            var next = i + 1;
            if (i == 0) {
                prev = n - 1;
            }
            if (i == n - 1) {
                next = 0;
            }
            if (arr[i] == 'S') {
                if (s[i] == 'o' && arr[prev] != arr[next]) {
                    fail = true;
                    break;
                } else if (s[i] == 'x' && arr[prev] == arr[next]) {
                    fail = true;
                    break;
                }
            } else {
                if (s[i] == 'o' && arr[prev] == arr[next]) {
                    fail = true;
                    break;
                } else if (s[i] == 'x' && arr[prev] != arr[next]) {
                    fail = true;
                    break;
                }
            }
        }
        if (!fail) {
            console.log(arr.join(""));
            break;
        }
        failCount++;
    }
    if (failCount >= 4) console.log(-1);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));