#include <string.h>
#include <stdio.h>
#define MAXN 10

int areaTot(FILE *fp) {
    unsigned int carte[MAXN][MAXN];
    unsigned int lx, ly, rx, ry, somma = 0;

    for (int i = 0; i < MAXN; i++) {
        for (int j = 0; j < MAXN; j++) {
            carte[i][j] = 0;
        }
    }

    while (!feof(fp)) {
        if (fscanf(fp, "%u %u %u %u ", &lx, &ly, &rx, &ry) != 4) {
            return -1;
        }

        if (lx >= MAXN || ly >= MAXN || rx >= MAXN || ry >= MAXN) {
            return -1;
        }

        for (int i = lx; i < rx; i++) {
            for (int j = ly; j < ry; j++) {
                carte[i][j] = 1;
            }
        }
    }

    for (int i = 0; i < MAXN; i++) {
        for (int j = 0; j < MAXN; j++) {
            somma += carte[i][j];
        }
    }
    
    return somma;
}

int main() {
    FILE * fin;
    fin = fopen("./carte.txt", "r");
    printf("%d", areaTot(fin));
    fclose(fin);
    return 0;
}