#include <stdio.h>
#define MAXM 100000
int x[MAXM], y[MAXM];
int main(){
    int n, m, k, i;
    FILE *fin, *fout;
    fin=fopen("stergeri.in", "r");
    fout=fopen("stergeri.out", "w");
    fscanf(fin, "%d%d%d", &n, &m, &k);
    for(i=0; i<m; i++){
        fscanf(fin, "%d%d", &x[i], &y[i]);
    }
    for(i=m-1; i>=0; i--){
        if(k>=x[i]){
            k+=y[i]-x[i]+1;
        }
    }
    fprintf(fout, "%d\n", k);
    fclose(fin);
    fclose(fout);
    return 0;
}