HJ8

var num = readline()
var arr = []
while(num){
    let str=readline()
    str = str.split(' ')
    let index = arr.findIndex((item)=>{
        return item[0]==str[0]
    })
    if(index == -1){
        arr.push(str)
    } else{
        arr[index][1] =parseInt(arr[index][1]) + parseInt(str[1])
    }
    num--
}
arr.forEach((item)=>{
    console.log(item.join(' '))
})