1049 기타줄

#include <stdio.h>
 
int main() {
    int n, m;
    scanf("%d %d", &n, &m);
 
    int line[51][2] = { 0 };
    int min6 = 1000, min1 = 1000;
 
    for (int i = 0; i < m; i++) {
        scanf("%d %d", &line[i][0], &line[i][1]);
 
        if (min6 > line[i][0])
            min6 = line[i][0];
        if (min1 > line[i][1])
            min1 = line[i][1];
    }
 
    if (min6 > 6 * min1)
        min6 = 6 * min1;
 
    int rst1 = 0;
    rst1 += (n / 6) * min6;
    rst1 += (n % 6) * min1;
 
    int rst2;
    rst2 = (n / 6 + 1) * min6;
 
    if (rst1 < rst2)
        printf("%d", rst1);
    else
        printf("%d", rst2);
}