UVa: 10920 - Spiral Tap

#include <cstdio>
using namespace std;

typedef long long ll;

ll p;
int sz;

int main() {
    //freopen("input.txt", "r", stdin);
    while(scanf("%d %d", &sz, &p), (sz || p)){
        ll increment = 1, current = 1;
        int line, column, x, y;
        x = y = sz / 2;
        while(true){
            if(current == p){
                line = y; column = x;
                break;
            }
            if((p > current) && (p <= current + increment)){
                column = x;
                line = y + (p - current);
                break;
            } else {
                current += increment;
                y += increment;
            }
            if((p > current) && (p <= current + increment)){
                column = x - (p - current);
                line = y;
                break;
            } else {
                current += increment;
                x -= increment;
            }
            increment++;
            if ((p > current) && (p <= current + increment)){
                line = y - (p - current);
                column = x;
                break;
            } else {
                y -= increment;
                current += increment;
            }
            if((p > current) && (p <= current + increment)){
                column = x + (p - current);
                break;
            } else {
                current += increment;
                x += increment;
            }
            increment++;
        }
        printf("Line = %d, column = %d.\n", line + 1, column + 1);
    }
    return 0;
}