#include <stdio.h>
int main () {
   int qx, px, qy, py, qz, pz;
    if(scanf("%d %d",&qx, &px) != 2 ||
    scanf("%d %d", &qy, &py) != 2 ||
    scanf("%d %d",&qz, &pz) != 2) {
        printf("Invalid input");
        return 0;
    }
    if(qx < 0 || px < 0 || qy < 0 || py < 0 || qz < 0 || pz < 0) {
        printf("Invalid input");
        return 0;
    }
    long total = (long)qx * px + (long)qy * py + (long)qz * pz;
    printf("%1d",total);
    return 0;
}