
/*
 * Return a count of the total number of objects 'o' satisfying o.x == o.y.
 * 
 * Parameter(s):
 * objects: an array of objects with integer properties 'x' and 'y'
 */
function getCount(objects) {
    var count=0;
    for(var i=0;i<objects.length;i++){
        if(objects[i].x===objects[i].y){
            count++;
        }
    }
    return count;
}


function main() {
    const n = +(readLine());
    let objects = [];
    
    for (let i = 0; i < n; i++) {
        const [a, b] = readLine().split(' ');
        
        objects.push({x: +(a), y: +(b)});
    }
    
    console.log(getCount(objects));
}