[백준] 6064번 : 카잉 달력 - C

https://www.acmicpc.net/problem/6064

#include<stdio.h>
#include<string.h>

int main() {
    int k;
    scanf("%d",&k);
    for(int i=0;i<k;i++){
        int m,n,x,y;
        scanf("%d %d %d %d",&m,&n,&x,&y);
        int num=x;
        
        while(1){
            if(num%n==y){
                printf("%d\n",num);
                break;
            }
            if(n==y && num%n==0){
                printf("%d\n",num);
                break;
            }
            if(num>m*n){
                printf("-1\n");
                break;
            }
            num+=m;
        }
    }
}